[
    {
        "key": "CRGGSG4M",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/CRGGSG4M",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/CRGGSG4M",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/JTQ9R9KQ",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "CRGGSG4M",
            "version": 1,
            "parentItem": "JTQ9R9KQ",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "JSTOR Full Text PDF",
            "accessDate": "2011-02-06T03:16:07Z",
            "url": "http://www.jstor.org/stable/pdfplus/748796.pdf?acceptTC=true",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "Secada et al. - 1983 - The Transition from Counting-All to Counting-on in.pdf",
            "md5": "da0cce937296d461c926bc0768675c41",
            "mtime": 1321544314000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:33Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "K25B5RF6",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/K25B5RF6",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/K25B5RF6",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/TFJIJGJS",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "K25B5RF6",
            "version": 1,
            "parentItem": "TFJIJGJS",
            "itemType": "attachment",
            "linkMode": "imported_file",
            "title": "2010--Fusch Powell Seethaller Hamlett Cirino Fletcher--A Framework for Remediating Number Combination Deficit.pdf",
            "accessDate": "",
            "url": "",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "2010--Fusch Powell Seethaller Hamlett Cirino Fletcher--A Framework for Remediating Number Combination Deficit.pdf",
            "md5": "e05f9072fb8aef698758f4681b0dbfbd",
            "mtime": 1321544314000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:33Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "8RTJINXQ",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/8RTJINXQ",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/8RTJINXQ",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/HVFKMK9R",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "8RTJINXQ",
            "version": 1,
            "parentItem": "HVFKMK9R",
            "itemType": "attachment",
            "linkMode": "imported_file",
            "title": "1988--Willis Fuson--Teaching Children to Use Schematic Drawings to Solve Addition and Subtraction Word Problems.pdf",
            "accessDate": "",
            "url": "",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "1988--Willis Fuson--Teaching Children to Use Schematic Drawings to Solve Addition and Subtraction Word Problems.pdf",
            "md5": "775dca9fb446bc5605618b21bca40778",
            "mtime": 1321544314000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:33Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "Z5R6CUHM",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/Z5R6CUHM",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/Z5R6CUHM",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/BWWXNEKR",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "Z5R6CUHM",
            "version": 1,
            "parentItem": "BWWXNEKR",
            "itemType": "attachment",
            "linkMode": "imported_file",
            "title": "1999--Rittle-Johnson Alibali--Conceptual and Procedural Knowledge of Mathematics- Does One Lead to the Other.pdf",
            "accessDate": "",
            "url": "",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "1999--Rittle-Johnson Alibali--Conceptual and Procedural Knowledge of Mathematics- Does One Lead to the Other.pdf",
            "md5": "b7af1e343f4920dfe0a904e37c554209",
            "mtime": 1321544310000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:30Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "PIDN25H3",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/PIDN25H3",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/PIDN25H3",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/7XGV4RKR",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "PIDN25H3",
            "version": 1,
            "parentItem": "7XGV4RKR",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "ScienceDirect Snapshot",
            "accessDate": "2011-11-17T15:27:53Z",
            "url": "http://www.sciencedirect.com/science/article/pii/S0361476X09000162",
            "note": "",
            "contentType": "text/html",
            "charset": "utf-8",
            "filename": "S0361476X09000162.html",
            "md5": null,
            "mtime": 1321544303000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "BAATZHFR",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/BAATZHFR",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/BAATZHFR",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/HSD44E2R",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "BAATZHFR",
            "version": 1,
            "parentItem": "HSD44E2R",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "ScienceDirect Snapshot",
            "accessDate": "2011-11-17T14:49:50Z",
            "url": "http://www.sciencedirect.com/science/article/pii/S0361476X97909620",
            "note": "",
            "contentType": "text/html",
            "charset": "utf-8",
            "filename": "S0361476X97909620.html",
            "md5": null,
            "mtime": 1321544303000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "58KE6Q4N",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/58KE6Q4N",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/58KE6Q4N",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/HSD44E2R",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "58KE6Q4N",
            "version": 1,
            "parentItem": "HSD44E2R",
            "itemType": "attachment",
            "linkMode": "imported_file",
            "title": "Path Analysis.png",
            "accessDate": "",
            "url": "",
            "note": "",
            "contentType": "image/png",
            "charset": "",
            "filename": "Path Analysis.png",
            "md5": "422f1117b03ab220eca279c11fbd766e",
            "mtime": 1321544303000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "AET385CQ",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/AET385CQ",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/AET385CQ",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/XBQAX36H",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "AET385CQ",
            "version": 1,
            "parentItem": "XBQAX36H",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "ScienceDirect Full Text PDF",
            "accessDate": "2011-02-07T00:50:53Z",
            "url": "http://www.sciencedirect.com.proxy1.library.jhu.edu/science?_ob=MImg&_imagekey=B6WJ9-4HV75VV-1-3&_cdi=6873&_user=75682&_pii=S0022096505001670&_origin=search&_coverDate=04%2F30%2F2006&_sk=999069995&view=c&wchp=dGLzVzz-zSkWb&md5=6cc92c30f2a84844e58944f348932aa2&ie=/sdarticle.pdf",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "LeFevre et al. - 2006 - What counts as knowing The development of concept.pdf",
            "md5": "651f72ddf73aa955906b8d17712ee97a",
            "mtime": 1321544303000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "882MX95Z",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/882MX95Z",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/882MX95Z",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/KCIQ26NG",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "882MX95Z",
            "version": 1,
            "parentItem": "KCIQ26NG",
            "itemType": "attachment",
            "linkMode": "imported_file",
            "title": "1998--Fuson--Pedagogical Mathematical and REal-world conceptual-support nets a model for building children's multidigit domain knowledge.pdf",
            "accessDate": "",
            "url": "",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "1998--Fuson--Pedagogical Mathematical and REal-world conceptual-support nets a model for building children's multidigit domain knowledge.pdf",
            "md5": "9ad841dc1bf9a550affbdd8b42e94ed1",
            "mtime": 1321544303000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "CCX92QXG",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/CCX92QXG",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/CCX92QXG",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/Z69EWE9V",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "CCX92QXG",
            "version": 1,
            "parentItem": "Z69EWE9V",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "JSTOR Full Text PDF",
            "accessDate": "2011-02-06T02:43:39Z",
            "url": "http://www.jstor.org/stable/pdfplus/40248053.pdf?acceptTC=true",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "Mcintosh et al. - 1992 - A Proposed Framework for Examining Basic Number Se.pdf",
            "md5": "af4ea28632b28f08025d8568c542faee",
            "mtime": 1321544302000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "96FR4WPK",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/96FR4WPK",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/96FR4WPK",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/4NK2488R",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "96FR4WPK",
            "version": 1,
            "parentItem": "4NK2488R",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "ERIC - Education Resources Information Center",
            "accessDate": "2011-02-06T01:30:29Z",
            "url": "http://www.eric.ed.gov/ERICWebPortal/search/recordDetails.jsp?ERICExtSearch_SearchValue_0=EJ880130&searchtype=keyword&ERICExtSearch_SearchType_0=no&_pageLabel=RecordDetails&accno=EJ880130&_nfls=false",
            "note": "",
            "contentType": "text/html",
            "charset": "utf-8",
            "filename": "recordDetails.html",
            "md5": null,
            "mtime": 1321544302000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "EC8AFFKI",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/EC8AFFKI",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/EC8AFFKI",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/4NK2488R",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "EC8AFFKI",
            "version": 1,
            "parentItem": "4NK2488R",
            "itemType": "attachment",
            "linkMode": "imported_file",
            "title": "2010--Davis Wagner--Feeling number- grounding number sense in a sense  of quantity.pdf",
            "accessDate": "",
            "url": "",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "2010--Davis Wagner--Feeling number- grounding number sense in a sense  of quantity.pdf",
            "md5": "f172b5a6730ce921a5ef891f448f2af0",
            "mtime": 1321544302000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "FNWFSMCN",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/FNWFSMCN",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/FNWFSMCN",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/CV4R3ZDU",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "FNWFSMCN",
            "version": 1,
            "parentItem": "CV4R3ZDU",
            "itemType": "attachment",
            "linkMode": "imported_file",
            "title": "UDSSI Triad Model.jpg",
            "accessDate": "",
            "url": "",
            "note": "",
            "contentType": "image/jpeg",
            "charset": "",
            "filename": "UDSSI Triad Model.jpg",
            "md5": "e1ed102ffe162d8aae36575d8bf86c82",
            "mtime": 1321544302000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "UVVZN84K",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/UVVZN84K",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/UVVZN84K",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/NKCUZEIE",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "UVVZN84K",
            "version": 1,
            "parentItem": "NKCUZEIE",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "SpringerLink - Educational Studies in Mathematics, Volume 27, Number 2",
            "accessDate": "2010-12-09T03:28:33Z",
            "url": "http://www.springerlink.com/content/k16u21152x255750/",
            "note": "",
            "contentType": "text/html",
            "charset": "utf-8",
            "filename": "k16u21152x255750.html",
            "md5": null,
            "mtime": 1321544302000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "AQ733X47",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/AQ733X47",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/AQ733X47",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/9W9PF5EG",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "AQ733X47",
            "version": 1,
            "parentItem": "9W9PF5EG",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "SpringerLink - Instructional Science, Volume 35, Number 6",
            "accessDate": "2011-02-06T02:10:44Z",
            "url": "http://www.springerlink.com/content/wm41812008368271/",
            "note": "",
            "contentType": "text/html",
            "charset": "utf-8",
            "filename": "wm41812008368271.html",
            "md5": null,
            "mtime": 1321544299000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:18Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "6S2KEA2H",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/6S2KEA2H",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/6S2KEA2H",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/BV9C5UHB",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "6S2KEA2H",
            "version": 1,
            "parentItem": "BV9C5UHB",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "JSTOR Full Text PDF",
            "accessDate": "2011-02-06T03:16:41Z",
            "url": "http://www.jstor.org/stable/pdfplus/749300.pdf?acceptTC=true",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "Fuson - 1986 - Teaching Children to Subtract by Counting up.pdf",
            "md5": "916419e16dbd4f764c70e5b3e7ca5985",
            "mtime": 1321544314000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:33Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "37IWJ4B4",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/37IWJ4B4",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/37IWJ4B4",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/2ZABJETM",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "37IWJ4B4",
            "version": 1,
            "parentItem": "2ZABJETM",
            "itemType": "attachment",
            "linkMode": "imported_file",
            "title": "1988--Fuson and Gordon B. Willis--Subtracting by Counting up More Evidence.pdf",
            "accessDate": "",
            "url": "",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "1988--Fuson and Gordon B. Willis--Subtracting by Counting up More Evidence.pdf",
            "md5": "5a514f9c8e4b9b4af7315cbdf929f95a",
            "mtime": 1321544314000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:33Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "EXTQR45P",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/EXTQR45P",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/EXTQR45P",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/DNEEHQJS",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "EXTQR45P",
            "version": 1,
            "parentItem": "DNEEHQJS",
            "itemType": "attachment",
            "linkMode": "imported_file",
            "title": "1998--Carpenter Franke Jacobs Fennema Empson--Longitudinal Study of Invention and Understanding in Children's Multidigit Addition and Subtraction.pdf",
            "accessDate": "",
            "url": "",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "1998--Carpenter Franke Jacobs Fennema Empson--Longitudinal Study of Invention and Understanding in Children's Multidigit Addition and Subtraction.pdf",
            "md5": "3fdacebb60429b5638daab50ce8b1fba",
            "mtime": 1321544313000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:33Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "RV6D6ST8",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/RV6D6ST8",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/RV6D6ST8",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/FQN4RBNJ",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "RV6D6ST8",
            "version": 1,
            "parentItem": "FQN4RBNJ",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "Google Scholar Linked Page",
            "accessDate": "2011-02-07T00:52:40Z",
            "url": "http://www.ingentaconnect.com/content/bpsoc/bjep/2009/00000079/00000003/art00005",
            "note": "",
            "contentType": "text/html",
            "charset": "windows-1252",
            "filename": "art00005.html",
            "md5": null,
            "mtime": 1321544310000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:30Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "NFKA7DV7",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/NFKA7DV7",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/NFKA7DV7",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/R5AWW89V",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "NFKA7DV7",
            "version": 1,
            "parentItem": "R5AWW89V",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "Google Scholar Linked Page",
            "accessDate": "2011-02-07T00:27:36Z",
            "url": "http://www.psy.cmu.edu:16080/~siegler/r-jhnsn-etal-01.pdf",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "Rittle-Johnson et al. - 2001 - Developing conceptual understanding and procedural.pdf",
            "md5": "2deb5855158e5c44896dec1c6e7f6546",
            "mtime": 1321544310000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:30Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "A9399SS3",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/A9399SS3",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/A9399SS3",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/7XGV4RKR",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "A9399SS3",
            "version": 1,
            "parentItem": "7XGV4RKR",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "ScienceDirect Full Text PDF",
            "accessDate": "2011-11-17T15:27:54Z",
            "url": "http://www.sciencedirect.com/science?_ob=ShoppingCartURL&_method=add&_eid=1-s2.0-S0361476X09000162&_acct=C000228598&_version=1&_userid=10&_ts=1321543516&md5=734961e9ec7b8f7fe6574f95239b5c91",
            "note": "",
            "contentType": "text/html",
            "charset": "utf-8",
            "filename": "science.html",
            "md5": null,
            "mtime": 1321544303000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "DI79TPGG",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/DI79TPGG",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/DI79TPGG",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/HSD44E2R",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "DI79TPGG",
            "version": 1,
            "parentItem": "HSD44E2R",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "ScienceDirect Full Text PDF",
            "accessDate": "2011-11-17T14:49:47Z",
            "url": "http://www.sciencedirect.com/science?_ob=ShoppingCartURL&_method=add&_eid=1-s2.0-S0361476X97909620&_acct=C000228598&_version=1&_userid=10&_ts=1321541251&md5=61a11a7271e723cd443470842d32a615",
            "note": "",
            "contentType": "text/html",
            "charset": "utf-8",
            "filename": "science.html",
            "md5": null,
            "mtime": 1321544303000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "9JDNFNT3",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/9JDNFNT3",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/9JDNFNT3",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/XBQAX36H",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "9JDNFNT3",
            "version": 1,
            "parentItem": "XBQAX36H",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "ScienceDirect Snapshot",
            "accessDate": "2011-02-07T00:50:55Z",
            "url": "http://www.sciencedirect.com.proxy1.library.jhu.edu/science?_ob=ArticleURL&_udi=B6WJ9-4HV75VV-1&_user=10&_coverDate=04/30/2006&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1632148834&_rerunOrigin=scholar.google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=5dd04e26e35b7f38863f0a2c911406a0&searchtype=a",
            "note": "",
            "contentType": "text/html",
            "charset": "utf-8",
            "filename": "science.html",
            "md5": null,
            "mtime": 1321544303000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "2GEQE5B4",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/2GEQE5B4",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/2GEQE5B4",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/DWASQ6TD",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            },
            "numChildren": 0
        },
        "data": {
            "key": "2GEQE5B4",
            "version": 1,
            "parentItem": "DWASQ6TD",
            "itemType": "attachment",
            "linkMode": "imported_url",
            "title": "JSTOR Full Text PDF",
            "accessDate": "2011-02-06T03:17:17Z",
            "url": "http://www.jstor.org/stable/pdfplus/749525.pdf?acceptTC=true",
            "note": "",
            "contentType": "application/pdf",
            "charset": "",
            "filename": "Fuson - 1990 - Issues in Place-Value and Multidigit Addition and .pdf",
            "md5": "e07c4c7bb8a7fe4bb660efa6c949b1d8",
            "mtime": 1321544303000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    },
    {
        "key": "J953MMPD",
        "version": 1,
        "library": {
            "type": "group",
            "id": 60460,
            "name": "primarymathematics",
            "links": {
                "alternate": {
                    "href": "https://www.zotero.org/groups/primarymathematics",
                    "type": "text/html"
                }
            }
        },
        "links": {
            "self": {
                "href": "https://api.zotero.org/groups/60460/items/J953MMPD",
                "type": "application/json"
            },
            "alternate": {
                "href": "https://www.zotero.org/groups/primarymathematics/items/J953MMPD",
                "type": "text/html"
            },
            "up": {
                "href": "https://api.zotero.org/groups/60460/items/KCIQ26NG",
                "type": "application/json"
            }
        },
        "meta": {
            "createdByUser": {
                "id": 5946,
                "username": "scottmessinger",
                "name": "",
                "links": {
                    "alternate": {
                        "href": "https://www.zotero.org/scottmessinger",
                        "type": "text/html"
                    }
                }
            }
        },
        "data": {
            "key": "J953MMPD",
            "version": 1,
            "parentItem": "KCIQ26NG",
            "itemType": "attachment",
            "linkMode": "imported_file",
            "title": "1998--Fuson--Conceptual Support Net.png",
            "accessDate": "",
            "url": "",
            "note": "",
            "contentType": "image/png",
            "charset": "",
            "filename": "1998--Fuson--Conceptual Support Net.png",
            "md5": "d899c6af215048fb68f7703591017efe",
            "mtime": 1321544302000,
            "tags": [],
            "relations": {},
            "dateAdded": "2011-11-17T15:38:21Z",
            "dateModified": "2011-11-17T15:39:32Z"
        }
    }
]