Well, anything from pre-K through eighth grade. Mostly physical sciences. I haul my stuff in ten-gallon plastic bins with lids. Sound is a very popular experiment, using homemade musical instruments on which we can play real tunes. We use a xylophone made from wood dowels, and another one made from electrical conduit pipe, as well as a set of panpipes made of plastic pipe from the plumbing section of the hardware store.
Electricity features hands-on electrical circuits with flashlight bulbs, wires, and batteries.
They really love when I bring out the doorbells, buzzers and tiny electric motors to connect up to their batteries. I know that I have not only entertained but also really taught them. I hope that my work will help some children learn to feel good about science even at an early age, so that they will feel that science is fun and is something that they can understand and do and succeed at, not something just to memorize and answer the questions at the end of the chapter. I hope to help teachers of self-contained classrooms to make science come alive for their children. So many of those teachers do not have a strong background in science and don't feel comfortable doing hands-on science beyond sprouting bean seeds in a flowerpot.