Theme: Get Outside!
We did some survival math, sunlight tracking and compass rose designs. You can find a straight line from West to East if you track the shadow of a stick and mark its top over time. Then you can find North and South and relate that to a compass rose on a map and find your way. We also aligned sticks with the rays of the sun to track the time and sun angles (from vertical). This is not only interesting on its own, but also a key component of Eratostheses calculation of the size of the earth in 200 BC.