Leonardo High School is the high school located in the center of Leonardo, New England. It is more academically-inclined than its biggest rival, North Leonardo High School, despite generally having an excellent wrestling team.

Leonardo High's mascot is supposedly the Llama, but their flags all show images of ostriches. Nobody really gets it. The school colors are black, grey and red. In the late 1980s, students began designing all of the schools' merchandise and uniforms after 8-bit NES controllers.

The following students have all attended Leonardo High:

• Dariaan Nighthawk
• Croc
• Beth
• Biff J. Rockenheimen
• Craig Aucoin
• John Vautour
• Camilla
• Julia Bovein
• Joanie Bovein
• Janet Bovein
• Bru Bovein
• Marsha Bovein
• Avril Bovein
• May Bovein
• Augusta Bovein
• Amber Bovein
• Tobi Bovein
• Nova Bovein
• Dodecahedron Bovein
• Wendy Greenspring
• Erik Thiessen
• Dane
• UV Granite

The following faculty have been known to work at Leonardo High:

• Mr. Johnson
• Ms. Cox
• Coach Carnage