- “I look like a grim reaper.”
- ―Anna in Tess Coleman's body
Anna is a 15-year-old high school student who appreciates sleeping in late, fashionable dressing, and her punk rock band. Her mother is Tess Coleman, who is a hard-working psychologist and writer that gets by with a collection of cell phones. She also has a little brother named Harry, who annoys her very much, especially when he enters her bedroom. Her main instrument is the guitar. Anna's best friends are Maddie and Peg, who are also members of her rock band.
Anna dresses in punk attire, usually with the colors red and black. She has dirty-blonde hair, fair skin, and wears a belly button piercing she hid from her mom before they switched bodies.
Anna is apparently herself in the beginning and the end. She argues with Tess a lot. One night when she, Tess, Harry, and Tess's fiancé, Ryan, go to dinner at Pei Pei's Chinese restaurant, Anna and Tess get into an argument. Pei Pei's mother comes with two fortune cookies, and as Anna and Tess open them, there is an earthquake only they feel.
The next morning, Anna wakes up in Tess' body. It happens that Tess woke up in Anna's body. They go back to the restaurant to see what happened. Until they get switched back to their own selves, they must do each other's positions. Anna goes to work as a psychologist. She is later being interviewed for a psychological book that Tess wrote. It is being filmed, and is on TV at her school, which embarrasses Tess.
At Anna's band rehearsal, Tess doesn't know Anna's performance; she doesn't even know how to play guitar. Anna plugs in an electric guitar backstage for her mom. After the rehearsal, Tess realizes that Anna's band is way more fun then she thought.
There is one more earthquake, and Anna and Tess are switched back in their own selves. Anna performs at Tess and Ryan's wedding.
- "You couldn't last one day in my high school."
- "You're ruining my life!"
- (as Tess) "Oh! I'm like the crypt keeper!"
- "GET OUT OF MY ROOM! GET OUT!"
- "What are you doing?, Get out of my room!"
- "You give me that door! Or I will kill myself"
- "Where's my door?
- Before Lohan was cast, a few other actresses were considered for the part of Anna Coleman.
- Originally Kelly Osbourne auditioned as Anna and was offered the part but decided to back out. Later, she said people told her it was the biggest mistake she'd ever made, due to the success of the movie.
- Michelle Trachtenberg was cast as Anna, but had to back out, due to her contractual obligations to Buffy the Vampire Slayer (1997).