Have you heard of Bedtime Math, a website that gives free daily math problems to solve?
You don’t have to do them every day but I like to read them so I can bring them up when convenient. Like, say, when we are hanging out at Lake Chargoggagoggmanchauggagoggchaubunagungamogg.
You can sign up for daily e-mails, which give a problem and three possible ways to handle it, one for “wee ones”, one for “little kids”, and one for “big kids”. So it works for various age groups.
Plus, Ninja Training!