In the third and final episode of the movie, Spinelli and her parents go to a pumpkin patch where Spinelli picks an ugly pumpkin for Halloween. Lawson and his gang are also at the patch, telling Spinelli that she is too old for Halloween and that they are only there to throw the pumpkins, not make them into lanterns. She too believes that she is too old for Halloween, and consequently asks her parents to leave. However, her parents tell her that they have to get a picture of her sitting on a giant pumpkin like they have done since she was a baby. Guilted into it by the baby pictures, Spinelli sits on the pumpkin, but it gives way and bursts under her weight. Seeing this, Lawson and his posse begin to laugh at Spinelli.
Back at school, where Miss Finster is dressed as a fairy princess (and coincidentally, Randall dresses up as a fairy prince, though it doesn't impress Miss Finster) and offers up yam cupcakes with prune icing, she starts up a song about a sweet-toothed vampire. At lunch, T.J. and the gang are talking about Halloween, Gus stuck on what he is going to wear, as Principal Prickly is dressed up as the former was planning to dress up as. Spinelli comes in and says that she is too old for Halloween, eating a lunch from home and going away. The gang remembers all the good times they had with her on Halloween.
Halloween finally comes and Spinelli's parents are going out while she is staying home. While she is watching a movie, the diggers knock on the door, see her expression, and tell her that they will tell the other kids to skip her house because she is not in the Halloween spirit. However, she tells them not to warn the other kids so that she can pretend she is scared. When the next lot of kids come and she pretends to be scared, the kids are not meant to be scary. In return, she scares them by wearing a scary mask and screaming "Take candy and go to the next house". She then closes the door smiling. When the next group of kids comes, she gives them tips for being dinosaurs by putting ketchup over their suits and telling them to roar from the stomach. The next trick-or-treater is a werewolf who howls and actually scares Spinelli. However, the werewolf takes off its mask and it is actually Miss Finster. She comes in looking for Spinelli's parents, giving her advice about Halloween and that some people, like her, never get too old for it. She then gives Spinelli her phone number in case her parents come home early, and then goes out trick-or-treating.
Meanwhile, T.J. and the gang are out trick-or-treating, Gus wearing toilet paper as a mummy costume. Their worries over Spinelli have ruined the magic of Halloween, along with the discoveries that someone (who turns out to be a dentist) is giving out sugar-free sweets, a building they thought was a haunted jail is really a closed down DMV, a zombie is really a robot, and gravestones are really just wood. They go home disappointed until Spinelli finds them and brings them to a home which they used to believe vampires inhabited. She persuades them to go in and the door locks behind them. Spinelli then goes into a door and screams while various monsters advance on T.J. and gang. One of them is the werewolf, who is once again Miss Finster in disguise and the other monsters are all the other teachers. They give the gang a heap of candy and the gang's Halloween spirit is restored, while outside Lawson and his gang are scared off by Miss Finster's wolf howl.
- This episode marks the final overall appearance of Miss Grotke and Hustler Kid, as they don't appear in Recess: All Growed Down (with the exceptions of the pre-made episodes in the movie.
- This is probably the third time someone in the series mentions a US state, this time being it Massachusetts, while the other two are probably Arkansas and Montana.