SpongeBob's Unicycle is SpongeBob's transportation until he gets his boating license.
SpongeBob first threw it into the dumpster at Mrs. Puff's Boating School, but later he gets upset when he did not have his bike to ride all the way back to the hospital to cheer up Mrs. Puff. Gary had found the unicycle and brought it back to SpongeBob. SpongeBob is also seen riding his unicycle again in "No Free Rides" and "Born to Be Wild."
He is last seen riding it in "Karate Star." It has a wave-blowing like wheel and pedals onto it. The unicycle can somehow ride fast because it takes less than three minutes to get to Mrs. Puff's Boating School, unless the Boating School is very close to SpongeBob's Pineapple.
SpongeBob is also seen riding his unicycle to school in "Demolition Doofus." In this episode, the unicycle is red.
The unicycle is blue and somewhat tall. SpongeBob called it a "bike," which is technically incorrect.