A little Halloween decorating idea from Popular Mechanics in 1935: make a “safe and cheap” jack-o-lantern from a balloon, a flashlight and some wrapping paper. Before you start, though, you have to blow up the balloon and paint on a grumpy Curly Howard face. You could make Moe and Larry lanterns to go with it.
I’m not sure where you would put this, since the flashlight has to be laid flat in order for people to see the balloon face. And someone also needs to be flashing the light on and off. I’m sure someone at your house will gladly volunteer to just hold the Curly balloon-and-flashlight and flick the on-off switch, all evening. And they can say “woo woo!” instead of “boo!” That will be fun.