I'm a huge believer in ART. It's a great creative outlet, fun, and even MOMS can join. One thing I do with my 1 year old daughter is finger painting. The boy, 4 months, is too young. It's best to wait until they are at least one...or when they don't put stuff in their mouth. Jeez, everything goes into the mouth with kids.
Here's what you'll need:
1. Big sheet of paper
2. Old clothes to paint in
3. Bucket of water for rinsing hands
4. Old towel to dry hands after rinsing
5. Finger Paint
PSSSST (If you're short on cash or materials you can get all of these items from Dollar Tree.)