Another favorite source of good dirty entertainment has been our sand box.
Everywhere we have moved we have built a sand box. Hours of building together and playing has been done in the sand box. The kids work together to make cities, ovens and food, rivers and mountains. My youngest one loves to recreate places we have visited.
Grandpa uses his tractor to till his sandbox and create a huge hill. The sand hill is always a favorite during every reunion. We finally have a sand box big enough, the house we bought in Utah had a sand volley ball court!! We have not yet volleyball in it but many, many hours have been spent in the sand.