Scratch.mit.edu
This is an interactive program that allows the user to select various variables and produces a spirograph-like shape.
Very simply, spirolaterals are spiraled, structured designs based on a repeated series of commands using length and angle.
Spirolaterals can range from very basic to elaborate, depending on the angle and number patterns used. The simplest type of spirolateral is a square — a 90 degree angle turn with a 1,1,1,1 sequence. It sounds complicated, but once you understand what’s going on, it’s very easy and fun to do.
What are Tessellations?
A student may not see a sequence of numbers but they may see a senquence of shapes, that's a tessellation.
Tessellations can be fun, beautiful, and mesmerizing. Check out this video on how to make one with your classes.