Parents are always interested to know when their teens should begin taking these tests. There is not a hard and fast rule. Often you can gauge when your teens are ready to tackle them. Since the math section covers material from basic math, Algebra 1, Geometry, Algebra 2, and some Trig, your teen will need to realize that these scores may be lower if he/she has fewer math courses completed when starting to take the tests. In light of that, it may be wise to consider completing at least Algebra 1 and Geometry before taking the tests.