This would work for educational games, math manipulatives, expensive reference books and resource materials too. I also Home school our 3 sons. I have found many books at Salvation Army for cents. It is a way to get rid of what you don't use anymore and find some that you use. They have a book fair every year with about 100 vendors.
Prices are cheaper and there are some used books too.
It gives lists of books you can find at the library to use. If you have more than one age group buy books that you can reuse. Just make sure they don't write in them. I also use my computer to make work sheets and tests. It takes some work but what better job could you have than raising your children.