Missing Miss Smith is an episode of the ALVINNN!!! and The Chipmunks series.
Alvin is bored with Miss Smith's lecture so he begins "organizing" his backpack. Following the class encouraging Alvin's behavior, Miss Smith attempts to start discussion about their book. The bell rings and Alvin tries to leave. When ordered back to his desk Alvin's scowl causes her to become twitchy and she leaves. Hours later the Principal informs them their teacher quit. At the Seville House Alvin sees he was the cause and decides to write an apology; Simon reads it and writes a real apology. The boys deliver the note to her house convinced it's enough to get her back though in class the next day find her absent. Derek thinks their new teacher is a pushover but is surprised to learn he's really a military sergeant who makes them do pliés for punishment. The Chipmunks go to her house again only to be shooed or issued a restraining order from Officer Dangus. After spying on Miss Smith, The Chipettes point out the obviousness between Alvin and Simon's words so Alvin writes another apology by himself. Alvin brings the entire class to her house to sing a song he wrote though they run away when Officer Dangus approaches. Alvin drops his letter while being carried away. The next day Miss Smith surprisingly returns to a well behaved class, and, once Alvin starts making a disturbance, the class yells "ALVINNN!!!"
- "Missing You" 
- Goof: Alvin's backpack is shown to be on his back but it disappears only to reappear in the next shot.
- This goof occurred in Mystic Mountain as well though with Simon's pack instead of Alvin's.
- When this episode premiered in the US, it aired with a rerun of Special Delivery.