Describe the parts of the atom. Explain that the atom is composed of three atomic particles: the positively charged proton, the negatively charged electron and the neutral neutron.
Explain that the protons and neutrons make up the core of the atom, called the nucleus. Like a raspberry, in which many individual fruits are packed together to form one fruit, the protons and neutrons are packed together in a small space to form the nucleus.
Explain that around this nucleus, electrons exist in orbitals. Note that these orbitals are not the same as Neil Bohr's orbits, in which the electrons move in a fixed path but rather are like clouds where the electron has a high probability of being at any one moment. There are many shapes and sizes of clouds where electrons can exist, depending upon the amount of energy they possess.
Describe how the proton behaves. Explain that the number of protons determines the element. Their positive charge also attracts electrons, which not only keeps the atom's own electrons from flying away but may also attract electrons from other atoms, which causes the atoms to bond into compounds.
Describe how the neutron behaves. Explain that the number of neutrons determines the isotope, or the variation, of the element. A normal atom contains the same amount of neutrons as protons. Isotopes contain more or less than this number.
Describe how the electrons behave. Explain that the number of electrons in a normal atom equals the number of protons, which causes their charges to cancel and creates a neutral atom. If the atom loses or gains electrons, it forms an ion, or a variation of the atom with a positive or negative charge. You may also want to note that electrons are involved in chemical bonding. When two atoms bond, they accept, donate or share electrons, which is how the world's compounds are formed.