I've had this huge bag of field corn in my house from last fall and the fall before that. I like to decorate with it, not in a Hansel-and-Gretel sort of way, but like filling up a dish with corn and nesting a tea light holder in the middle of it. Wait--do I need to explain myself? My cupboards hold a lot of odd things. Useful-some-day things.
One day when the kids needed something new to do, I pulled the corn out of hiding. I poured a little into two 9x13 pans and gave them each two measuring cups, a toy tractor and a funnel. They enjoyed their own personal corn boxes so much, we made two more for when their cousins came to play. Their progression of interest was entertaining. At first, the older cousin wasn't interested at all, and the other three played happily in their own pans. Then the three got together at the same pan, and the one on the outskirts realized the fun he was missing. So he joined. And then they naturally progressed back to their own pans when they got in each others' way. Now doesn't that look like fun? You could do the same thing with wheat or rice. The only hard part is putting it up when stuff-everything-in-his-mouth boy Jack wakes up from his nap.