This is the 3rd bonus level played by the Skater. It is unlocked after collecting 15 bonus levels.
If you don't want the bonus, this level is easier than Level 2. All you have to do is jump. It is self explanatory.
To get the bonus, you must catch onto the right side of the spawning platform, fall down onto the one that has the bonus, then continue. When jumping under the main platforms, be careful not to touch them, as this almost guarantees failure. It requires precise timing. The jumps are also quite long, and at the end you need to jump and catch on the underside of a platform to finish the level.