GPA Notes 7/23/09 Who: Walter, Caroline, Jennifer, Anurag 10:45: Set-up computers and projector. Walter worked on Clock program in Turtle Art Walter: Today we are going to use the turtle to play with clocks. (Walter shows the kids the clock program he made in Turtle Art. The kids compare Walter's clock with the other clocks in the room. Walter: Why do we use 12 numbers on the clock instead of 10 or 6 or 5? Kids: Because there are 24 hours in the day and 12 is half of it Walter: The Egyptians came up with the idea of 12 hours at day and 12 hours at night. (Walter showed kids how to count to 12 using the different parts of their fingers. Walter talked about the Babylonians and said that they liked to use the number 60.) Walter: Today we are going to use the turtle to play with hours. The kids used the following sequence to make the turtle point in different hour directions: seth() --> forward(100) -- back(100) Note: The kids started off by experimenting with different values for "seth" I feel most kids struggled with this because they had not learned too much about geometry, particularily concepts involving degrees and radii. However, kids experimented with a lot of different values to better predict increments. Some kids realized that if they input a really large number they would get the same result as importing a really small number (ex: 12 and 732). As expected, the kids did not understand why that was. Perhaps we need to give a brief geometry lesson before letting the kids play with heading directions. -- Anurag Goel