The world of college admissions has seen monumental changes over the past few years, and test-optional policies are at the center of this evolution. If you’re the parent of a high school student, chances are you’ve heard about test-optional policies and wondered: What does it really mean? Is it truly optional? And could it hurt my teen if they don’t take the ACT or SAT?

Let’s break it all down so you can feel confident in your decisions about standardized testing—and ultimately set your teen up for success.

First, let’s clarify: Test optional doesn’t mean test blind. Colleges that are test-optional allow students to choose whether to submit standardized test...