The Suite Life of Zack and Cody
Barbara was first seen in, "Rock Star in the House". She built a baking-soda volcano and had entered it in a sceince fair. She entered a spelling bee in "Neither a Borrower Nor a Speller Bee", where she misspelled fracas and was eliminated, and worked on the school paper in the episode "Ask Zack". Barbara likes Cody; in the episode "Club Twin", she becomes addicted to sugar and kisses Cody. She goes on a few dates with Cody, as seen in, "Miniature Golf" and "A Tale of Two Houses". Barbara is Cody's girlfriend in a few episodes.
The Suite Life on Deck
Barbara is mentioned in, "Parrot Island". When Cody and Zack admit that they both like Bailey, Zack tells Cody that he was dating Barbara. Cody says that he told Barbara that they might fall in love with other people when he left for the boat.
Barbara visted the S.S Tipton in the episode, "Flowers and Chocolate". She started dating Bob, Zack and Cody's friend, sometime after Zack and Cody had left for the S.S. Tipton. When Barbara arrives on the ship, she is afraid to tell Cody about her relationship with Bob, thinking that he is still in love with her. However, Barbara is unaware that Cody has fallen in love with Bailey.
When Barbara meets Cody, she eventually tells him that she is dating Bob. Feeling jealous, Cody lies and tells Barbara that he is dating Bailey. Barbara suggest that they double-date, and Cody reluctantly agrees. They go to see a movie being played on the ship.
During the movie, Barbara was possibly jealous of Bailey, because she seemed angry at her. When Barbara tells Cody to tell Bailey to stop talking, she calls Bailey Cody's girlfriend. They both find out the truth. Bailey and Barbara become upset and they both leave. Cody isn't seen apologizing to Barbara, but he does apologize to Bailey. Cody and Barbara do make up however.
Barbara is very academically competitive, as shown in "Graduation". Though she's likely not as smart as Cody, she is considered the second most clever person in their class. She is also feisty and used her karate skills to threaten to hurt Cody in, "A Tale of Two Houses" if he tried to push their relationship too far.