We made "cannons" out of 7 pop cans. Cut the ends off 6 of them so they were just tubes. On the 7th, use an old can opener to punch 4-5 triangular holes in one end and put a nail-hole in the center of the other closed end. Duct-tape them all together with the single hole in can 7 at the end. Then tape them all to some kind of a long stick you could hold onto.
Squirt about 4 long squirts of lighter fluid in the single hole, grab the stick and swing the hole thing around over your head, and it's ready to go. Hold a lit stick or something to the little single hole and...KABOOM!! The cannon would fire!!
Put a tennis ball in the open end and do it all again. You could fire that ball over the neighbor's house across the street!! The game was whose cannon was the loudest or could shoot a ball the farthest.
How did we survive??!!