His science model was clearly made by him. Most of the others clearly weren't.

Class 5 science exhibition last week. My son made a water filter from a cut bottle, sand and gravel, entirely on his own, crooked label and all. Half the table had models that looked like they came from a shop. He got a participation certificate and came home asking why his friend's volcano won when "his dad made it". I teach older students and I know exactly how I'd feel marking that table. What I don't know is what to say to a 10 year old. "Your work is yours" sounded thin even as I said it.