Research proved Legos make kids smarter.
For smaller kids : colors and shape. For older kids : Creativity and imagination.
A child’s brain is like a sponge, ready to soak up whatever touches it. For this reason, you should surround children with positive, educational experiences. Toys that develop cognitive skills include role-playing activities, like playing house or being superheroes. Building toys, like blocks or Legos are also good for cognitive development. Exploration toys, like magnifying glasses and games with rules also enhance cognitive development in children.
Read more: Toys That Support Cognitive Development | eHow http://www.ehow.com/list_6931694_toys-support-cognitive-development.html#ixzz2TDrcW79f
Check your school, local library for Lego club.
Lego ideas : http://legoquestkids.blogspot.com/