Horace Cheseborough or more commonly known by his title name of Mr. Cheseborough is a recurring supporting character in the television show. A grumpy science teacher and homeroom teacher who works in Conestoga Hills Middle School and later Conestoga Hills High School, Mr. Cheseborough becomes the unsuspecting victim of the battles between the Lightning Knights and the Carnival of Doom. Mistaking the characters from the Sixth Dimension as aliens, Mr. Cheseborough becomes more and more paranoid that they are out to get him, to the point where he seems to go mentally insane. He is often turns to his student Mark Hollander for help regarding the "aliens".