The Secret Snake Club vs P.E. (S07E03)

When Billy discovers that the members of the Secret Snake Club are using phony doctor's notes to skip Physical Education, he decides he wants in on the action. All the boys join the club, and with the help of Billy's dad, who pretends to be a physician, they secure their excuses, leaving Billy as the lone participant in gym class. Meanwhile, the Snake Club attempts to unleash chaos by summoning a snake to wreak havoc in the gym. However, when the creature turns out to be too small, Sperg employs Grim's scythe to enlarge it. Ultimately, Mandy and her friends triumph over the boys and their serpent, as they value P.E. as a crucial outlet for their energy.