Amby's Brain Games & Thinking Skill Enhancers-.an assortment of learning activities, computer puzzles and games to play online (or download), as well as IQ tests and personality assessments. http://amby.com/go_ghoti/thinking.html
Categorized archive of challenging, fun, and exciting Brain Booster from Discovery School! http://school.discoveryeducation.com/brainboosters/
All you need is a sheet of paper and a brain. Links containing a puzzle with a finished picture. Your goal is to fold the puzzle into a shape with a solid color on each side. http://www.teachnet.com/brainbinders/