One thing I really like about Descartes Cove is the "secret" book with definitions in it. That way, if DS needs to know a definition (what is a perfect number?) to do a problem, it teaches him not to just throw up his hands and say, "I don't know how to do this!" Instead, we can look it up in the book or use the gold coins to buy a hint.
I've also let him use a calculator for some calculations that he doesn't know how to do yet. The problems take us a long time (and a lot of diagrams and scratch paper) to do. But he seems to enjoy them because they are not repetitious.
