First I went to a home and garden store and bought two round 20lb pavers for a couple of dollars each.
Next I painted them white.
The white was just to give the girls a base to work on while they painted. While the layer of white acrylic paint was drying I prepped paint (acrylic), brushes, water cup and paper towels for the girls.
Then they painted. There was a bit of a learning curve for painting on top of the texture, but they had so much fun it didn't matter to them very much.
Next a quick coat of varnish for weatherproofing. I will leave them in the garden for the summer, but I will probably tuck them under the patio for shelter from the winter weather, which will probably start next week.