Haley Grille is one of the students who attended Summer School.
Haley Grille has made two appearances in The Suite Life of Zack & Cody, in the episodes: Summer of Our Discontent and later in Benchwarmers. At Summer School, Zack notices Haley. He greets her and asks her name, but she says she is shy and puts a bag on her head displaying: Haley. Throughout the episode she is known to being painfully shy; when everyone was looking at her she threw up. Haley was one of the students in the class that bullied Zack becuase he was the only student who actually tried. Later on, when Mark needed tutoring, she shows up with the rest of the class at Suite 2330 wanting help in schoolwork. (becuase she usually gets 'F's'.) Back at school, when everyone passed, the class thanked Zack. Haley said, "I love you", indicating that she had a crush on Zack.
Haley then appeared in Benchwarmers. She tried out for the Cheerleading Squad, but Dana Wool rejected her. This urged her to join the "Rebel Cheerleaders", a team of Cheerleaders who were not good enough. So she (along with Cody, London, Leslie, Barbara and Nia) challenged the real cheerleaders to a "cheer off". Due to crown reaction, the "Rebel Cheerleaders" won. Additionally, Haley claimed that she once hid for 4 weeks without anyone finding her. Throughout these episodes, Haley's last name was unknown until the closing credits of Benchwarmers and it is revealed as "Grille".
The common trait about Haley is that she wears a bag over her head most of the time, due to her shyness. Usually it is a paper bag, but when she came up to Suite 2330 she was wearing a fancy bag. Haley Grille wears average clothes, and she has long, brown hair.