June 28, 2005

At the beginning of the class, David demonstrated basic probability by flipping a coin several times. After analyzing the results, the students determined the probability of heads on each coin flip. Then, David showed the students how to figure out the probability of winning a game of rock paper scissors. To illustrate probability, the class played a game where everyone was a seedling trying to grow up. To grow into a bush, two students would play a game of rock-paper-scissors, and the winner grew into a bush. If they won again they would become a tree. After they finished the bush game, David showed the class an applet that simulates a forest fire. The student could set the probability that a tree next to a tree on fire would burn down, and see what percentage of the forest burns.

After snack, David explained how to model the spread of a disease using NetLogo. After setting various factors such as the amount of people and the recovery rate, they saw how diseases, like chicken pox, spread. They discovered that a disease with a longer duration and a lower mortality rate is more dangerous than a disease with a short duration and a high mortality rate. Then, they repeated the activity using Vensim, an alternative modeling program.