You just realized that one of your target schools requires all test scores to be submitted. But what about that one really low SAT score you got back in tenth grade? How are you going to explain that?

Actually, you don't have to. “They are what they are," says Evelyn Alexander, a Certified Educational Planner and founder of Magellan College Counseling. “We don't recommend that you try to explain scores anywhere."

But will that one low score affect the way the school looks at your application? Probably not. Usually, schools that ask for all of your tests just want to see how you have progressed academically throughout your high school years.

“It's very unlikely that one bad score will negatively impact your chance of acceptance," Alexander says. "But you need to think about the pool of applicants at each college to which you apply. If you are considering highly selective colleges with very small acceptance rates, keep in mind that many, if not most of the applicants, will have very high scores. These schools reject thousands of applicants with PERFECT scores. There's just no guarantee that comes with high scores, and this is another reason that you must have a balanced list of colleges."

Most Schools Don't Want All Scores

Of course, it helps to know that there are actually very few colleges (usually the most prestigious) that actually do require you to submit the results from all of your test sittings. Below is a list of some colleges that ask to see all of your scores -- SAT, ACT or both. But if you are considering applying to one of these schools, call the admissions office to confirm if this policy has been changed or updated. While the website may state that all test sittings are "required," you might talk to someone at the school who says it they are only “recommended" and not required.

- Georgetown: Requires all SAT, all ACT and all SAT subject test scores.

- Stanford: “Requirement" not explicitly stated on website; will superscore SAT and for ACT but “we will review all subscores and focus on the highest Composite from all sittings."

- Barnard: Requires all SAT and ACT scores, but not SAT subject test scores; will superscore SAT.

- Yale: Requires either all SATs or all ACTs, or all scores from both exams.

- Cornell: Requires either all SAT or all ACT scores, will superscore SAT.

- Carnegie Mellon: Requires either all SAT or all ACT scores only from junior or senior year test dates.

- Rice: Expects all SAT and ACT scores, but not technically required: “We hope applicants will report all scores knowing that we will recombine the sections to get the best possible set of scores for each candidate."

- University of California: Requires all scores from either SAT with Essay or ACT with Writing.

- University of Miami: Requires either all SAT or all ACT scores; does not require SAT subject tests.

Don't forget that more and more colleges are actually going test optional, while others superscore without any strict requirement for sending in all your scores. Because of these varying requirements, it's very important to target a mix of colleges.

Check Test Stats at Target Schools

Alexander says students should not apply solely to colleges “whose middle 50 percent test scores are significantly above yours. This is a recipe for disaster. We would call this a 'reach-heavy' list, and it honestly means you are more likely to be rejected than to be admitted to those schools. You should spend a good chunk of your junior year researching colleges, as there are over 2,200 four-year colleges in the United States. Allow yourself to choose just a few of those super-top reach schools. Students whose lists aren't balanced are the ones who are most disappointed with their results. So having a balanced list will help ensure that you have choices in the spring of your senior year."

Take at least a couple practice tests before the test date so you already have a general idea of what your scores will be on the official test. Alexander recommends taking the SAT or ACT at least two times, but feel free to take it three times if you feel you can do better.

“When you think about it, it's hard to imagine that colleges would penalize you for taking an SAT or ACT, and then taking it again and improving. I guess the real question is this — why would you want to go to a college that thinks poorly of you for taking a test again and trying to improve your score?" Alexander explains.

If you're still feeling worried about your low score, Alexander advises students to always look at the big picture and not to concentrate on test scores alone.

“Colleges are generally much more interested in how you've performed over three years in high school, and what you're taking your senior year as you continue to challenge yourself, than in how you perform in one 3.5-hour test," she said. "You should absolutely study and prepare! But remember that your college applications are supposed to show you as an entire package: grades, test scores, teacher recommendations, activities lists and essays. Who are you? How have you arrived here? What are you hoping to do in your future? And what will you add to a college community? Colleges will explore all of these things as they decide whether or not you would be a good addition to their freshman class."