June 23, 2005

Simon began by explaining that since a circle has 360 degrees, an n-gon has 360/n degree angles. For example, a square has four sides, so each angle of a square is 90 (360/4) degrees. He then split the students into teams of two, and assigned each team to a computer. Every team wrote a program in Logo that drew an n-gon. After the class finished that, Simon explained that recursion could be used make fractals in Logo. Fractals are a geometric pattern that repeats at smaller and smaller scales. Simon demonstrated by drawing Koch's Snowflake, a figure created by deforming the sides of triangles again and again. Each team then created their own fractal by implementing recursion.

After snack, everyone showed the class their favorite fractal. Then, Simon showed the class how to use the keywords "and" and "or" in their recursion. After that, Simon announced a contest. The first team to create a grid of at least 20 equilateral triangles would win two bags of Oreos. After awhile, Simon showed them various hints, and ran his program in slow motion to help them out. However, no team was able to finish the challenge, so they saved their progress and agreed to continue the next morning.