Position Donkey Kong Jr. directly under a dirt section on the "pelicans" level. Climb all the way up to the dirt, then move him left, right, and left . At that point, move Donkey Kong Jr. left, right, and left again to climb through the dirt section.
Invisible vine
Begin game play on the "springboard birds" level. Jump to the top ledge on the right and approach the gap. Walk off the ledge at this location to grab an invisible vine that may be used to climb to the top of the screen.