## Circles and Figure 8s

We continued working on our lesson 1 worksheet. We had previously been exploring how we can control the robot through rotations, degrees and seconds. Today we began making more connections using math.

Many students were able to complete this challenge, but it was all from guessing. When we stopped to talk about the math, they realized how the circumference could be used to determine how many wheel rotations were needed to make it to 20 inches.

We will continue more challenges where they need to recognize the connections between their math and programming skills.

**Circumference**

We had students find the circumference of their wheels. Many of them figured out how to program the robot to move the wheels 1 rotation. By doing so, they measured from the starting point to the end point to calculate their circumference. This information was used in a later challenge.**Challenge: Make a Circle**

We had a task for making the robot complete a circle. Many of the students programmed the robot to turn 360 degrees. However, this only makes the wheels turn 360 degrees which is the same as the wheels making one revolution. They quickly found that this did not make the robot turn a complete circle. Most found that somewhere around 1000 degrees made the robot spin a complete circle. Furthermore, they found out that if done on the tile vs. carpet yielded different results.**Challenge: Drive forward 20 inches, turn 180 degrees and drive back**

On this challenge students had to use their understanding of circumference to determine how to make the robot go 20 inches. For example, if they found that their wheel circumference was 6.5 inches, then they could have determined that 3 wheel rotations would yield 19.5 inches. They should have programmed their robot to drive forward 3 wheel rotations. (They had to have kept their speed the same as when they found their circumference or it wouldn't have worked. Fast you go, the farther you travel).Many students were able to complete this challenge, but it was all from guessing. When we stopped to talk about the math, they realized how the circumference could be used to determine how many wheel rotations were needed to make it to 20 inches.

We will continue more challenges where they need to recognize the connections between their math and programming skills.