In this learning module from The Concord Consortium, students will learn how to figure out whether an object has a positive or negative charge.

Wikipedia provides the definition of the term, "Atomic number," a term used in chemistry and physics to represent the number of protons in the nucleus of an atom.

A relatively easy set of instructions for building a Leyden jar, and an easy-to-understand explanation of how it works.

Resource explains how to build and use a simple electroscope.