My son started learning algebra at age 4, even before starting to learn multiplication and division. I don't believe in the idea that children aren't able to think abstractly enough to learn algebra until roughly age 10. Once you get over a few basic concepts (what a variable is, what an equation is, etc.) you are ready to begin in earnest.
EDIT: OP, I agree with BWBShari, CAMom, and ColinsMum (and you). I think that thinking abstractly is actually one of the most important things to introduce early in any course of study. I want my kids to have an instant reflex for abstraction when they encounter something new.
Last edited by Iucounu; 09/25/10 09:02 AM.