Shelby Rose Cummings is one the main Antagonist in the movie. the most popular girl in Sam's school and cheerleader captain. She has to tolerate Sam's stepsisters Brianna and Gabriella because they gave her a Prada bag for her birthday. Her best friends are Madison and Caitlyn. Shelby torments Sam and calls her "Diner Girl". She used to be Austin Ames's girlfriend and manipulated him into doing what she wants. Austin dumped her before the Halloween Homecoming Dance. When Brianna and Gabriella lied to Shelby by saying Sam tried to steal Austin and show her Sam and Austin's emails, she immediately becomes jealous. When Shelby and the stepsisters expose Sam's secret and humiliate her in front of the whole school, she's delighted by the chance to get back together with Austin but he ignores her and keeps his distance from her. At the homecoming game, Shelby gets her comeuppance as Austin falls into Sam's arms and Shelby becomes heartbroken and angry. At the end of the movie, she tries winning Carter, after he is seen in an acne commercial and is popular but Carter dumps her for another girl, after seeing her true colors from when she humiliated Sam.
Shelby is very mean and spoiled but very glamourous. She dislikes Sam and Carter very much. Shelby makes fun of Sam just because she worked as an employee at the diner Hal used to own. Shelby always gets what she wants, and she's very selfish. She may look nice on the outside, but she's incredibly ugly on the inside.
Name: Shelby Rose Cummings
Physical Appearance: Tall, long blonde hair, mean girl
Occupation: Head cheerleader
Personality: Rude, selfish, irresponsible, spoiled, greedy, careless, desperate, evil
Allies: Brianna, Gabriella, Madison and Caitlyn
Quote: "Love her dress. Hate her"