Cool Math

Tap the Web for activities.

George likes these: National Library of Virtual Manipulatives (nlvm.usu.edu), which organizes math activities by topic and grade level; Interactive Mathematics Miscellany and Puzzles (cut-the-knot.org) and Cool Math (coolmath.com)

Source: http://www.freep.com/article/20100908/FEATURES01/9080345/1374/FEATURES/Change-your-math-attitude-and-daughters