Johnston, Tom

Illustrates the properties of electricity and its development as a vital energy source.

Demonstrates the many uses of water, where it comes from, how it is wasted, and why it is vital to the survival of living things.

Illustrates the properties of air, how air works for us, and how we use and abuse it.

Explains the phenomenon of color, how it is perceived by the eye, and how it is important to humans, animals, and plants. Includes some simple experiments and projects.

Explains how forces such as gravity, friction, elasticity, and inertia and agents of force such as leverage and balance affect our lives.

Examines energy in its variety of forms, how one form of energy converts into another, and alternative energy sources that may lie in the future.