I would suggest having them try a sample test for each. The full test, with real timing, breaks, etc. Much of the material is similar, so the practice will benefit both. The time pressure (time per question) differs, so some people struggle to complete one but are OK with the other. I've read, though can't confirm, that ACT contains more advanced math - some trig and advanced algebra - which would would suggest that the SAT might be better. Though that also means that the scoring bar for any type of admissions process would also be lower.

Last edited by Cranberry; 11/18/16 10:20 PM.