Mr. Johnson is the not-so-popular gym teacher at Springfield Elementary.
Before Milhouse flew away in a hot air balloon with his uncle Norbert Van Houten, he had told students that their journey would be better than gym with Mr. Johnson, making students laugh. Mr. Johnson then told them that climbing a rope was really important.
When Bart learned that Milhouse wanted to fly away, he caught a rope, but didn't know how to climb it. Satisfied, Mr. Johnson asked his students what they thought about his rope climbing lesson now, but Bart and Milhouse called out that it still sucks.