Set the Goal System to Variable since you have more line to fill before leveling up in the long run. Gotten the achievement with 200 line with a score of 50,335. Just keep the grid low. Like Elem3ntal said, "go for clearing the entire grid because I believe you get 10,000 bonus when you do this." I managed to get this achievement without clearing the bottom. Also, hit the up button after you line up the pieces, so you could get drop points.