I love kids' hand print crafts. The small, personal feature captured forever... It gets me every time. We have framed hand prints, clay impressions of hand prints, even a class plate with a painted hand print.
So, when these cheap pots went on sale, I ran out and bought my favorite shiny paint colors. A fun out of paint, handprints, and way too much mess followed. I got these at Michael's, bit any craft paint should work. As long as you seal it. Seriously.
Don't skip the sealant step. Like, really, really don't skip it. Otherwise the paint flakes off, gets in the potting soil, and you've got a big mess! Believe me, impatient moi tried skipping that step and I had to redo the whole thing.