Sneak in some summer math along with rock play! Paint the rocks together- any toy they’ve helped to create will be more ‘attractive’ and get used. You’ll probably have to add the numbers and symbols, but your child will still be invested in those rocks. Then, the math fun can begin.
There’s lot of ways to play with these that teach a range of math concepts: bigger and smaller, matching numbers to their meaning (the count of the symbols), putting numbers together to make bigger numbers ( a 2 and a 4 makes 24), and if you make enough rocks, simple addition and subtraction.
Before you or your child knows it, lots of math has been learned and practiced.