Paul S. Bodine, Author/Consultant Specializing in Medical & Business School Admissions
I'm assuming that you think you won't "make the cut" because your GMAT score is significantly below the median of the top schools (the top 10 average 710 or higher). If this is the case, then keep in mind that business school admissions committees do not treat GMAT scores as boxes to be checked. They don't have strict cut-offs, and if your profile is really strong or unusual you may still get admitted to good schools. "Strong" means, for example, you started a very successful business or nonprofit or have some other very clear and unusual mark of success in addition to a good academic record (strong grades tell the schools that you are just one of those people who don't do well on standardized tests). "Unusual" could mean you are an Underrepresented Minority (African American, Hispanic American, Native American, Pacific Islander), you are from a country that rarely sends applicants to top schools, or your career has been in an extremely unusual profession such as professional sports, etc.
How do you decide which non top-tier schools will be good for you? Using your GMAT score as a rough guide, draw up a short list of schools whose median or middle range scores match yours. Next, ask yourself what criteria are most important to you in an MBA program---geography? faculty strength in a specific discipline? tuition cost? specific target firms that regularly recruit at the school? average MBA placement rate or typical salary? Prioritize these criteria and use a business school guidebook and school websites to find out which schools match your criteria. Then start reaching out to these schools' students, alumni, and admissions officers and visit the schools if you can.
Don't let rankings influence your short list too much. Remember that the difference between a top 3 school and a top 15 school is more perceptual than real -- you can achieve your goals at non-top-tier schools if you choose wisely, strategically. For example, if you know what job market you want to work in, choose non-top-tier schools in that market that feed that city's employers. For example, Chicago---a major job hub---is home to top-tier schools like Chicago Booth and Kellogg, but it also has other quality business schools such as DePaul, U. of Illinois at Chicago---even regional schools with strong Chicago networks such as U. of Illinois Urbana Champaign and Notre Dame. Even though they are not super-brand programs, these local schools can help you target local employers very effectively.