Kevin, the student that the twins exposed for murdering the class pet iguana, was originally named Todd, but the writers changed his name last-minute to avoid confusion with the identically-named robot that appears throughout the series.
Leni's teacher is the only one that is unknown, as their name is neither mentioned in the dialogue nor on the Loud parents' chart. However, a later episode (despite having been produced before this episode) would reveal that one of her teachers is named Mr. Rickshaw.