Each summer, my son and I have a general theme. Nothing big, just something to give our time a little educational direction. For example, one summer was Warrior Summer. We picked Friday night movies based on knights in shining armor or kung fu masters or samurais. Books from the library had some sort of warrior character. We even signed him up for a weapons class to supplement his regular karate lessons.

One of the best summers we had was when I decided it was going to be Ballistic Summer. In the first week, we built a catapult out of PVC pipe. We’re off to a good start. We read about and made matchstick rockets. Don’t bother, while interesting in concept, a matchstick that shoots five to eight inches is not that entertaining.

I mention to a friend who’s the kind of a guy who flies glider planes and owns two Ferraris, that I’m doing research to build a potato cannon and of course he has done it and has some ideas. Then we discuss the possibility of making homemade gunpowder and he gets really excited, “I love to blow stuff up.” I reply, “What guy doesn’t?” His next comment, “I don’t trust a guy who doesn’t like to blow stuff up,” floats around my head whenever I meet someone new.

A couple of weeks later, my friend calls and proclaims, “It’s here!” “What’s here?” “The potassium nitrate.” It’s one of the more difficult elements to get, used to make homemade rocket fuel aka gunpowder. (I’m sure it has other purposes, but they can’t be as cool as what we’re doing.) He had to search several web sites and “probably ended up on a terrorist watch list,” but he’s ready to make something go boom. We set a date and using a bunch of stuff around the house, we make a very cool homemade rocket pinwheel. In the next few weeks, we launch rockets at the school playground and explode small homemade firecrackers (really closer to M‑80s) in the backyard.

We survived the summer with all our fingers in tact, no knocks on the door from homeland security (although I’m sure this post has set off some alarms), discussed fuse delays and secondary rockets on 4^th of July and even had time to watch October Sky. We never quite got around to the potato cannon, but all in all a pretty good summer.