This site has a bunch of fantastic DIY carnival games .and activities. including this simple GUESSING BOOTH.Love the guessing booth idea as students come in and LOVE the signs.
Boys Circus Themed Birthday Party Can Toss Game Ideas, ring toss
Ping Pong ball Nerf targets--easy to make with some weighted water bottles and ping pong balls. We definitely have the nerf guns to do this!
How to Make a Nerf Spinning Target - Fun game for a Nerf birthday party! Great boredom buster too. This would be great for a superhero party, too.