The materials you need
All you need is a square piece of plywood any reasonable size, and a post that you can make from a broomstick, a piece of dowel wood, or any square piece of wood, we took a 2×2 centimeter piece of pine, about 5 inches or 12 centimeter long. Drill a hole in both ends to receive the nail, one to nail the post to the base and the other to act as the shaft for the rotor.
The medicine cups you can get at any drugstore, just ask for a few, three is enough, but you may want some spares. We melted a hole in the bottom for the screw instead of drilling a hole. I used a piece of steel wire from a coathanger and heated the end up with a gas flame, but a candle will work also, when the end is hot stick it through the bottom, don’t make the hole too large! You need some supervision by an adult with this!
The coloured sticks are from a craftstore, you can also use medical tongue depressors, they are the same size but not coloured. You should be able to get these parts easily. Drill a small hole in each stick for the screw that holds the cup onto the stick.
The hub is cut from a sun umbrella post, you can use any round or even square piece of wood, in this case cut or sand off the four corners to make it look better. You need to cut a slit in the hub at three locations divided around the circumference of the hub. Just use a small hand saw to make the cuts. You may need some help dividing the circumference by three, but most highschool students can help you, by dividing a circle by its radiius you get six divisions, pick every other division and you have the three you need. They should be 120 degrees apart. Nice geometry lesson …