I don’t know about you, but around here, a.) cacti and succulents are very popular, and b.) my kids cannot paint enough rocks. As there are very few crafts they seem willing to do, I’ll let them paint as many rocks as they’d like!
You can get a BIG bag of rocks from your local big box home improvement store for $10-$20 dollars; the pots are from Pat Catan’s for about sixty cents apiece. Have fun!