I know your child may seem so young to you still but carnival is going to seem quite juvenile to them and their friends unless you do it big and go allll out. I work with middle schoolers on a regular basis. If you decide to do carnival I would suggest using games where they can earn tickets at different games, such as popping balloons with darts, fish bowl w/ping pong balls, corn hole, etc and they can turn the tickets in to pie (whip cream) either friends or even funnier, you, in the face, a dunk booth, and games of that nature