Great activity that grows with your child... Younger kids just fit rocks in by size, older ones can match colors or letters. Both ages can play side by side. I'll start now with just the sizes and some rocks since my guy is obsessed with them.
Cloud Dough - (the stuff at hands on museums) 8 cups flour & 1 cup baby oil. It feels like flour as you run your fingers through it, but it's mold-able. A wonderful sensory activity for children. So cool