A hands-on approach to introduce the chemical elements and the atomic structure to elementary/middle school students is described. The proposed classroom activity presents Bohr models of atoms using common and inexpensive materials, such as nested plastic balls, colored modeling clay, and small-sized pasta (or small plastic beads).

A number of concerns have been raised by researchers regarding the use of models in science classrooms. Those concerns have largely been raised in studies involving interviews with students and teachers. In this article, I address issues that surfaced through my examination of classroom teaching episodes; two of these episodes and their associated…