When I was teaching in Ravenswood I had a classroom budget of zero, and a bunch of mismatched math books. What our school did have however, was a laminating machine. I put this to good use making as many file folder math games as I could. These were a hands-on way to help my English Language Learner students learn to solve word problems, and gain conceptual understanding of multiplication and division.
You can make file folder games at home for your children too, concentrating on any math skill you like. Staple a ziplock bag on the back of the folder to hold all of the pieces. I left almost all of the games I made back at my old school, but I did keep a few examples.