This is a glitchy achievement. To begin...go to your console memory and delete the NCAA Gamer cache (your profile will regenerate when you next start the game with default settings). Only change the difficulty level to All-American, no other changes.
Now you have two options to complete the achievement:
1) Pick a good team for yourself (North Carolina, Duke, etc.) and a poor team as an opponent (any class D team should suffice), then play the game legit. If you win, the achievement will unlock.
2) The easy way...set up two controllers (go to play now and set up your team on controller #1 vs. an opponent on controller #2). Play against your opponent and rack up points. At about 1-2 minutes remaining in the second half, switch the second controller to CPU control (press start-->settings-->select side-->move controller #2 back to center, press B, finish game). The achievement will unlock after the congratulation handshakes.
If you negatve vote, please explain. There are no perfect solutions; however, every solution can be improved upon.