this seems like a really great site, chock full of very interesting articles - educational research, looking at how the brain works.

Here's one on how gesturing can help math learning...there seem to be several related articles.
http://www.sciencedaily.com/releases/2009/02/090224133204.htm

and 'Learning From Mistakes Only Works After Age 12, Study Suggests'
http://www.sciencedaily.com/releases/2008/09/080925104309.htm