A lot. When’s the last time you went camping with a bunch of zinc and copper nails, much less a supply of fresh lemons? It might be easier to put some matches in a waterproof canister ...

There are a whole bunch of high school science experiments out there that are useful for teaching students the basics of biology, physics, and chemistry. One of the classics is the lemon battery.

Firstly, prepare the lemons. Carefully cut lids off the whole lemons and using a juicer/reamer, squeeze and push out all the juice and pulp into a bowl. Trim the base of the lemon shells (so they ...