Cleveland teen Wren and her best friend April get invited to a Halloween party thrown by the hottest guy in school. Unfortunately, her mom makes her watch her little brother Albert during the night. He gets lost and Wren goes through the whole town searching for him while he gets caught up in a little adventure of his own.
It was the directorial debut of Josh Schwartz, and the second Nickelodeon movie to be rated PG-13.
Fun Size provides examples of:
- Annoying Younger Sibling: Albert
- The Alleged Car: Roosevelt's moms' Volvo.
- Asian and Nerdy: Peng, Up to Eleven
- Between My Legs: Shot shown frequently in the commercials, of the girl cosplaying as Galaxy Scout.
- Cool Loser: Wren and April.
- Cover Innocent Eyes and Ears: When the cops approach Jorgen's house, Wren covers Albert's eyes when Fuzzy flashes and runs naked to get their attention.
- Darker and Edgier: Definitely edgier for a Nickelodeon movie.
- Deadpan Snarker: Both Wren and April.
- Disappeared Dad: Wren and Albert's father is deceased, and Wren, Joy, and Albert's personal ways of coping with his death are their defining character traits.
- Extremely Short Timespan: The movie starts on Halloween morning going into the next morning.
- Grave-Marking Scene: Towards the end of the movie Wren and Albert visit their dad's grave and leave a small plastic pumpkin on his grave (because Halloween was their dad's favorite holiday).
- Groin Attack: Albert delivers one to Jorgen.
- Grounded Forever: Wren, being a teenage girl caught up in the situation she's in, thinks she'll be grounded "until she's 93" when her mom gets home and doesn't see her (and Albert) there.
- Halloween Plot: The plot takes place during Halloween night and the next day.
- Has Two Mommies: Roosevelt has two moms. They're also Hippie Parents.
- Hollywood Nerd: Roosevelt. He has an obsession with E.O. Williams, even dressing up as him and speaks Greek to both of his mothers.
- Not What It Looks Like: This is assumed when Fuzzy finds Albert in front of the convenience store:Fuzzy: I am not trying to lure a kid into my car!
- A man gets caught reading Fifty Shades of Grey.
- One Crazy Night: Four friends go on the hunt for a missing boy on Halloween en route to the biggest party of the year. The boy is having adventures of his own.
- Pair the Spares: April and Peng hook up by the end.
- Police Are Useless: The cops are more focused on busting Wren and her friends rather than catching the kids toilet papering their squad car.
- Prank Call:The last scene shows how Albert has been prank calling his mom for six months. It takes her that long to figure it out.
- Precision F-Strike: An S-bomb is dropped four times.
- This Is for Emphasis, Bitch!:Fuzzy: Trick or treat, bitch!
- Toilet Humor: A fair amount.
- The Voiceless: Albert is going through a selective mute streak until the last minutes of the movie when he thanks Wren for taking him trick-or-treating.
- Who Names Their Kid "Dude"?: Wren has this impression about her mom's boyfriend Keevin.Wren: It's not even a name, Mom. You're either Kevin or you're Steven, Keevin does not exist.