Yesterday, after we dropped the others off, we headed straight for the hardware store. I am not overly familiar with that particular store, though it was a little exciting to see the raw materials for so many potential science projects all lined up in neat little bins (my husband tells me those items are actually intended for some sort of home improvement - but I'm not convinced, it looked like a science supply shop to me).
Anyway, we plunked down three dollars, left with a length of plastic pipe (1/2 inch PVC), two elbow fittings, one T joint, and a slip cap (all the 1/2 inch variety). And, after a small struggle to get the pipe to fit into the mini van, we were all set to head home and make a marshmallow gun. This is one of those projects that you can find instructions for all over the web. It seems to be a favorite of the Boy Scouts, though they usually make the larger variety, for jumbo marshmallows.
We unloaded our pipe and fittings into the garage. Then, we grabbed a ruler, a marker, some sandpaper, and a hacksaw, and set to work. From the pipe, we cut two sections that were three inches long, and three sections that were two inches long. We used the sand paper to remove the rough bits from where we had cut.
Then we put the gun together, slipping the three inch pieces into sides of the T joint, and the two inch pieces and the cap as shown in the picture below.
All that was left, was to load up a marshmallow. They go in at the top, right where you blow. My son found that he could load as many as five marshmallows at once, for some rapid fire action. I took a minute to explain the science behind his new toy, demonstrating that the marshmallow goes farther when it is placed at the beginning of the pipe, rather than at the end, because of the amount of air pressure that is allowed to build up behind it when you blow. There is a very nice explanation of this, and a simpler version of the experiment, that does not require PVC pipe, at www.exo.net/~donr/activities/Marshmallow_Puff_Tube.pdf.
Of course, when the other children got home, they all wanted one too. So much for the bag of marshmallows I was going to use to make Rice Krispy treats with. It looks like we're in for a full out marshmallow war (especially since Daddy has put in an order for one too).
It's great to be a homeschooler!