Indoor "Sand" Box

This is so easy!  I emptied some rice into a casserole dish.  I found another container to keep next to it (it's an aluminum dish).  We added some spoons and measuring cups and tubes we've been saving for another project and the 6yo has had so much fun!:

Just in case you were thinking: "what is that black stuff?  mouse poo??"  (which is what I thought when I took a second look at the photos).  It's just a mix of different kinds of rice (whew!)

You could also use dried beans.  Be prepared for a little spillage, but it's SO much better than actual sand.  :)