What's a tessellation? Tessellations are patterns of a repeated shape arranged so they cover a complete plane leaving no space. A checkerboard is a tessellation, as are the Student Tessellations at this Math Forum site. The work of the graphic artist M.C. Escher, which might be familiar to some students, contains many examples of tessellations.

Tessellations are not just pretty to look at; they are a great way to teach such concepts as reflection, rotation, and translation. And�they're fairly easy to make. Walk your middle or high school students through the steps below to create their own tessellation with Excel.

Note: See Where's the Math for some lesson ideas and pedagogical background.

Next: Creating the basic polygon.