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You might find my YouTube series

Elementary Mathematics (K-6) Explained

useful, the Playlist so far is at

Feb 14, 2013 6:09:56 PM Feb 14, 2013 6:09:56 PM wildberger@pacific.net.au 0 http://mathforum.org/kb/thread.jspa?messageID=8325658&tstart=0#8325658
I'm trying to put together a list of free videos for adult education teachers to demonstrate the use of various math manipulatives]]> Feb 14, 2013 4:15:12 PM Feb 14, 2013 4:15:12 PM notesforfred@yahoo.com 1