The human battery experiment can be used to show students that electricity can be made with a chemical reaction. To do the experiment, mount a copper plate and an aluminum plate to two blocks of wood. Connect one of them to the DC terminal of a microammeter and the other one to another terminal. Place one hand on each plate and you will see by looking at the meter that an electric current is being generated. The sweat on your hands acts like the acid in a battery and makes a chemical reaction with the metal plates. You are taking negatively charged electrons from the copper and transferring them to the aluminum plate.
Lightning can be made on a small scale with a pie plate. You need a ballpoint pen, a thumbtack, a wool sock and a small piece of Styrofoam. Push the thumbtack through the center of the pie plate up from the back. Insert the pen onto the tack and secure with glue, if needed. Take the wool sock and rub the Styrofoam rapidly. Grab the pin to pick up the plate (do not touch the plate) and put it on top of the Styrofoam. With the lights out, slowly bring your finger close to the plate. You should be able to see a spark and even see and hear it.
To demonstrate Newton's Second Law of Motion, which says that an object's acceleration depends on force and mass, you can build a small car. Materials needed include two blocks of wood, approximately 1O-by-2O-by-2.5 cm and 7.5-by-5x2.5 cm, three round head screws (3-inch, No.10), 12 pencils or short dowel rods, three rubber bands, some cotton string, matches, 6 fishing sinkers, a drill and bit, vice, screwdriver and meter stick or tape measure. On the large piece of wood, screw in two screws close to each of the two corners on a short side and the other screw in the middle of the opposite side. Drill two holes in the smaller piece of wood that are big enough to drop two sinkers into. Make a small loop with a piece of string and place it over the rubber band. Put the rubber band over the two screws and pull the string over the other screw, like a slingshot. Put the pencils under the block and mark their positions. Put the smaller block in between the rubber band. Light a match and touch it to the string and the small block will fly off the other block. Measure how far it goes and how far the larger block moves. Repeat with two and three rubber bands and varying numbers of sinkers.
An experiment can also show inertia, physical forces on an object and energy transfer. Put a rubber band through an empty spool of thread and attach it to one end with a tack. Pull the other end through a metal washer and slip a matchstick through the rubber band. Wind the rubber band around several times until it is tight, then let go and see what happens. Experiment with different numbers of twists on the rubber band and a sloped surface.