When people say that test prep is ‘teaching to the test,’ I agree that it is always a good idea to know the mechanics, timing, and content of a test before you take it. Teachers provide study guides for this very reason.
However, there is an additional benefit to taking a test preparation class in school, with a good tutoring organization, or with a one-one tutor:

-Students refresh their memory of concepts they need for college, but haven’t seen since 8th, 9th, or 10th grade. Think grammar or geometry.
-Students become better at reading and better at comprehending the gist of what they read quickly. We use that skill in many professions every day.
-Students practice –sometimes learning for the first time — how to read data in charts and graphs.
-Students learn and master executive functioning skills such as pacing, deciding when to stay with an item and when to go, and learning and applying strategies.
The college-entrance exams ACT and SAT are both based on standards, just like the curriculum in your school. The ACT calls their standards College and Career Readiness standards, and they are exactly that: what a college freshman needs to know to succeed in college and career.
So hire that experienced tutor with confidence that you are providing your child much more than help reaching a test score and access to his or her dream school and scholarships. You are also supporting his or her academic foundation.