We recently dug up three small trees in our back yard to get rid of them. And when I say we, I mean Taylor. I didn't help at all. But Noah really wanted to help. So Taylor gave him a garden spade and he had a great time helping scoop dirt out from around the trees and moving it to Daddy's pile.
Apparently when the tree is gone, the hole it leaves behind is a great place to sit and look for worms and bugs.
As long as most of the dirt and all the worms and bugs stay outside and don't come in the house, I'm happy to let him play and get dirty.