Materials:
- fan (any size should work, but I prefer the college-dorm-style box fans)
- straws
- craft sticks
- different kinds and weights of paper
- rulers
- tape/ glue
- paperclips/ binder clips
- index cards
- other miscellaneous items to inspire student creativity
With students working in collaborative groups, each group will design a windmill that will generate the most energy (aka harnesses the most air and therefore rotates the fastest). Students can experiment with the size and also the shape of the windmill blades. To make the activity more challenging for older students, add a requirement that the total area of the blades can not exceed x.
As students work through the design process, they will not need to design a foundation for their windmills. While students are in the building process, they will need to mark one blade to make it easy to count revolutions when placed in front of the fan. When it is time to test, each team can either hold their windmill or use a large binder clip to affix it to the back of a chair. Windmills should be placed 60cm away from the fan set on high.
Once everything is in place, students can count the number of revolutions the blades make in one minute. Students can redesign their windmills twice, each time testing and hopefully increasing the number of blade revolutions each time. With their final design, teams will compete against each other to see which windmill blades competes the most revolutions in 2 minutes.
So, what did we learn? National Science Standards: Abilities necessary to do scientific inquiry, understanding about scientific inquiry, properties of objects and materials , abilities of technological design, understanding science and technology. NCTM Standards: Understand measurable attributes of objects and the units, systems, and processes of measurement, Apply appropriate techniques, tools, and formulas to determine measurements, Formulate questions that can be addressed with data and collect, organize, and display relevant data to answer them, build new mathematical knowledge through problem solving, Solve problems that arise in mathematics and other contexts, Apply and adapt a variety of appropriate strategies to solve problems, monitor and reflect on the process of mathematical problem solving. Other Skills: Communication, critical thinking, observation, collaboration.
