The easiest way to make a giant Plinko board for school carnivals or backyard fun. How to make a Plinko board.
This site has a bunch of fantastic DIY carnival games and activities. including this simple GUESSING BOOTH.
This can be a roomful of hay (or shredded paper, paper leaves, anything) with small objects hidden, or more like a bin as pictured. Trick-or-treat baskets or pumpkins would be cute too.