You know what I've just recently come to realize? Many of the supporting characters on ALVINNN are genuinely unlikeable much of the time. Miss Smith and Miss Croner, in particular, are prone to this: Miss Smith often goes out of her way to be harsh with Alvin, even when he doesn't deserve it - automatically singling him out for stealing everyone's phones and yet still punishing him after he proved himself guiltless, punishing him for Brittany getting that suck toad stuck on her face when he was actually pushed into the terrarium; Miss Croner goes back and forth between being an embodiedment of a miserable old lady who pesters kids for amusement, and being a misunderstood loner with a heart of gold - the switch witch prank was okay, because she and Dave were both in on it to give the kids a harmless scare for Halloween, but that cat curse prank to get the kids to find her missing cat for her was just spiteful, mean-spirited, and they even had to prompt her to thank them for even finding her cat. Derek? Again, he's just walking status quo, and nothing more. Even the other kids at school can be obnoxious at times.
Officer Dangus, Julie, and the seemingly nameless principal are just about the only consistently good supporting characters, though we seem considerably less of them.