Our "Earth" was candy bars and when we used a straw to take core samples of snickers bars, zero bars, and Take 5 we learned that each core sample can look different. We then cut cross sections of the candy bars and wrote scientific expositories of what kinds of rocks we saw (ie nougat was likened to magma and peanuts were like boulders). I'd say we had a fun science day and even better was that we ate the core samples...a treat in itself!
I wish I had learned science this way, I think I would have enjoyed science much more.