Take out a large baking pan [I use to keep a large tin turkey roaster on hand for this.] On a grander scale, try a shallow plastic storage tub [great because the lid makes it reusable for long periods without getting spilled or spoiled].Fill with cornmeal . Add some baking spoons, measuring spoons, cups, a few funnels… even a small sand toy will work.
I used to hide some small plastic or rubber toys [my kids used to love small cars, toy dinosaurs, and jungle animal figures. They would scoop and funnel and sieve until they discovered their “finds” and then play in their make believe world.
Whether I used cornmeal, or rice [my favorite], or even oatmeal…. I didn’t have to worry if they put some in their mouths during the process.
Image credit and thanks to: mamabeefromthehive.blogspot.com, steadymom.com