First, did you keep your second score? If not, please reinstate the score!
We have been hearing many reports lately of schools
liking the fact that students take the test multiple times. It shows perseverance, determination, dedication. We have had several reports of students with just a single test score that wasn't at or above a school's average getting dinged and being told after that one factor was that they didn't even try to take the test again. (eg, if a school's average is 720 and the person scored a 700 once - they were sometimes told that it was a negative that they apparently hadn't even tried to get a higher score, knowing that they were below that school's average.)
At those same schools, we've had reports of people getting in with scores below the school's average...and they've taken the test multiple times. Even though they didn't get up to the average, the school knew that they would work hard.
So get that 680 back on your record.
Next, if you feel that you have hit a wall, then some targeted help may be quite useful. A boot camp would set you back about $2,500 to $3,000 (depending whether in person or online). You could do approximately 10 to 12 hours of tutoring for that same amount. You'd get more raw hours in boot camp, but tutoring hours would be more targeted at what you need.
If you've already gotten yourself to a 680, then a lot of the bootcamp hours will be spent on stuff you already know. So I wouldn't do bootcamp. I'd choose between tutoring and self-study.
There are steps that you can take here to try to come up with a better study plan (for free), but it sounds like you think you may have already tried those things. If that's the case, then I'd suggest that you look into tutoring. But if you think you haven't tried everything here yet, then here are your next steps.
First, read this (right now):
https://www.manhattangmat.com/blog/inde ... lly-tests/Are you actually taking the test that way? Or are you still using the old school mindset, trying to get everything right? The vast majority of people who study and study but don't improve are still using the old school mindset.
Next, read this (right now):
http://www.manhattangmat.com/blog/index ... -the-gmat/Are you studying in this way?
Think about how what you've been doing does and doesn't match up with that and how you may need to change your approach accordingly.
Then, use the below to analyze your most recent MPrep CATs (this should take you a minimum of 1 hour):
http://tinyurl.com/analyzeyourcatsBased on all of that, figure out your strengths and weaknesses as well as any ideas you have for what you think you should do. Then come back here and tell us; we'll tell you whether we agree and advise you further. (Note: do share an analysis with us, not just the raw data. Your analysis should include a discussion of your buckets - you'll understand what that means when you read the last article. Part of getting better is developing your ability to analyze your results - figure out what they mean and what you think you should do about them!)