If you went to two different colleges where you achieved different awards, then I’d put them separate. It doesn’t matter if they overlap, you can always explain how and why at the interview stage, or in your covering letter. If there was a year where you didn’t attend one of these colleges, then came back to the same college, I’d hyphen 2006 – 2012 if these are the correct start and end years. Again, you can always explain the whys and wherefores at the interview stage. You’re not lying, you’re simplifying.