Spin Art Force STEM Activity

Poke one hole through one side of the cup near the top, then poke a matching hole directly on the opposite side.

Thread a piece of string through both holes, then tie the ends together in a knot at the top. This is your main cup.

Tie on more string above your first knot to extend it. Predict: Why do you think a longer string on a single, fixed point lets the cup swing freely in every direction instead of just front-to-back or side-to-side?

Find a place to hang your pendulum where it will have full range of motion, a few options: taped off the corner of a desk, hung from a broom or rod balanced between two chairs, tied to a tailgate or car bumper, or hung from the top of a garage door with an extra-long string for a bigger swing.

Set up your art station: lay down cardboard or a tarp to protect the floor, then place a large sheet of paper on top so it’s centered under where your pendulum will hang.

Poke a separate hole through the center of the bottom of the cup, pushing the pencil down and through so the paint can flow out. Predict: What do you think this hole needs to look like for paint to flow freely once you add it?

Loop a long string through this bottom hole and tie a knot near your other knot, then hang the cup from your chosen support. Mix your first paint color with a little water to thin it so it flows easily, and pour it into the cup.

For your first color, don’t change anything, just pull the pendulum back a bit and let it swing naturally as a baseline. Observe: As gravity pulls the cup back and forth, what kind of pattern does the paint trace on the paper? What happens to the loops as the pendulum slows down?

Empty any leftover paint, refill with a new color, and swing again, but this time change one thing on purpose (how far back you pull it, or the direction you swing it) before you let go. Repeat for each additional color, changing a variable each time.

Let your artwork dry, then compare the lines each color made. Observe: Which lines are smooth and solid, and which are made of dots or splatters? What might explain the difference, how far the pendulum swung, how thin or thick the paint was, or whether the hole got clogged?