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BTW, I never took the SAT - what level of Maths do the questions go up to? Wondering when my DD10 will be ready to try it...
Short answer -- I'd say Algebra II. The SAT is changing, starting spring 2016. You can read about the new math SAT at

The Redesigned SAT (section IV) and
Evaluating the New PSAT: Math

Khan Academy https://www.khanacademy.org/sat says it will have study material for the new math SAT in June of this year.