In the start menu choose the second option (Xbox Live), now the third option (create a lobby), in the top left the third option (exam) now press a to start the game mode. For this achievement you have to complete the 17th stage (to unlock this you have complete all the others before 1-16).
In this mode you must clear 4 Tasks:
1. 20 lines in 60 Seconds
2. 5x 3 Lines
3. 1 Line, 2 Lines, 3 Lines and a Tetris ( 4 Lines) you can choose the order.
4. 40 Lines in 1.40 Minutes in Hypermode (extreme fast)