I had a mud kitchen cabinet when I was little. My grandma stocked it with cookie cutters and bowls and all the things you see here. It sat near the spigot of an artesian well that produced the coldest, clearest water needed for the best mud cuisine.
Outdoor play! drains and gutters, exploring gravity and weights, using different balls and sticks, and rocks, I think toddlers would really enjoy the noise and dropping something and seeing where it comes out.