I build two of these rigs from PVC pipe . . .
Look, you can still see the splatter marks on the wall
from our recent fly swatter painting sessions!
. . . string, a few links from our plastic chain set, and a plastic cup with a hole poked in the bottom.
I've learned that every gallon of tempera paint has a slightly different consistency, but you normally need to dilute it with water so it flows properly. The jug we were working off this week needed to be about 2 parts paint to 1 part water. Of course, it also makes a difference how big you make the hole in your cup. I used a Phillips head screw driver to do the job.
As the kids approach the table, the art parent puts her finger over the hole to prevent the paint from spilling out prematurely, fills the cup about half way with the thinned paint, and hands it over to the child saying something like, "Give it a swing."
The results tend to be frame worthy:
I've tried making the paint even thinner, but if it's too thin, the paintings dry "fuzzy" as the excess water tends to absorb into the paper as it separates from the paint a bit. Of course, thinner paint does nothing to reduce the child's experience, but this is one of those few art projects where Woodland Park parents say they really want to take one home to hang on their walls, so I go with thicker paint in the hope of creating a few of these keepsakes. Also, I usually pre-tear dozens of sheets of butcher paper to have stacked under the pendulum so that all the adult has to do is whip one away to reveal a blank canvas for the next artist. Not only does this help give kids their turn without a lot of waiting, but it also helps keep the table from becoming a big pool of black paint while you're changing out the paper.
Between the Pre-3 and 3-5 classes, we made at least 100 of these artworks over the course of the past two days forcing us to be very creative in finding enough flat surfaces to dry them (for obvious reasons they can't be hung to dry). We went through an entire gallon of black paint and had to resort to blue by the end of the day yesterday. By this stage, the only painters left were a clutch of hard core scientists who were being quite intentional in their efforts. I wanted to share a few of these because you can see more complexity and evidence of different swinging techniques being employed. I even heard Anjali say, "I'm trying to make a butterfly."
I think this is the butterfly.
Annabelle achieved this by, in part, holding onto the string and swinging the cup
in a kind of chaotic manner.
Not all of them turned out looking like something from an art gallery . . .
. . . but that was hardly the point of this lesson in physics.