Have your students build a a functional windmill using a variety of materials for the lowest price possible. The windmill needs to be free standing, each team will be given a small electrical motor and use a hairdryer as the constant wind source. When you test the windmills, you determine the milliamps produced by using an amp meter. Once the students have built their windmills they present them to the village elders (aka, you and the rest of the class). This activity includes the student activity page, cost breakdown page and a four section rubric. Students love this activity and its cross curricular links allow you to cover science and language arts expectations.