start them young
I had a picnic last weekend and my 4 yr old GD was here and so was my friend with his 5 yr old. I thought craft time might be a good ice-breaker for my often shy GD. I spray painted some flower pots white and gathered up some paints, brushes and crafty supplies ahead of time.
Pretty soon the big kids joined in. I was a bit surprised when Sam the 17 year old said "Do you have any pots that I could paint?"
I was selfishly thrilled when the little ones each left 1 pot behind.