Here is the first public draft of the progressions project, on Number and Operations in Base Ten [corrected version uploaded 26 May 2012]. We welcome any comments or suggested changes, which will be considered for the final draft. Please post comments to this thread. We will be releasing other draft progressions for elementary and middle school over the coming weeks.
[29 July 2012] This thread is now closed. You can now ask questions on this progression here.