Hi Latichever:
In my DS case, when he was 10 and in fifth grade we changed schools and DS was put into Algebra class. It was a challenge for him for two reasons :1) we never did anything "ahead" in math at home, so he really never worked a lot with fractions before 2)it took him forever to complete homework - and it was a lot of homework and everyday. But he perserveered and by Christmas everything was back to normal - meaning he was again ahead of others (this time eight graders) in his math class.
He is now in 7th grade and taking Algebra 2/ Trig.
After seeing though what he is learning at school, how superficial everything was, we started supplementing with online classes at Art of Problemsolving (www.artofproblemsolving.com).
He is also participating in Math Olympiad, AMC, Math Kangaroo, Math Matters.
I have learned so far that it is very difficult but mighty important to keep a balance between my son being challenged to the extend of his abilities and yet not racing too fast through the curriculum. A very, very difficult thing. Please read
http://www.artofproblemsolving.com/Resources/AoPS_R_A_Calculus.php
Good Luck,
Ania