Matter, elements, and atoms (Click title for link)
This article is a perfect and easy to understand introduction to an atom. Not only does it introduce an atom as the most basic unit or building block of an element, but it also states that nearly everything in this world both living and nonliving is made up of atoms. The article goes into the structure of an atom and how it is made or protons and neutrons and electrons. It also goes briefly into defining matter and elements. This is a nice article to share as an introduction to chemistry and the atoms, elements, and matter.