<Li> An unnamed chemistry teacher at East High . She is portrayed by Irene Santiago - Baron . </Li> <Li> Ms. Falstaff is a librarian at East High . In the first film, she constantly reminds Chad to keep quiet in the library . She is portrayed by Joyce Cohen . </Li> <Ul> <Li> Jackie, Lea, and Emma are Sharpay Evans' friends, sometimes called the "Sharpettes". The girls are sometimes collectively known as the Sharpettes, as they often act as back - up singers and dancers for Sharpay, but are never referred to as such in the film series . It is apparent that they do not attend East High School and spend the majority of their time with Sharpay during the summer at her family's country club, Lava Springs . They seem to be equally as pampered as Sharpay, but always follow her every order . Jackie, Lea, and Emma are only portrayed in High School Musical 2, by Tanya Chisholm, Kelli Baker, and McCall Clark, respectively . Baker had a role as a cheerleader and dancer in the first film . </Li> <Li> Boi is Sharpay's dog who appears in High School Musical 2, High School Musical 3: Senior Year and Sharpay's Fabulous Adventure, Boi is taken to New York with Sharpay . He is given an opportunity to participate in a play called "A Girl's Best Friend" on Broadway, which Sharpay initially believed was her opportunity until the casting agent clarified her mistake . Boi meets another dog called Countess and they fall in love with each other, but their owners initially fail to see their affections . He is portrayed by director Kenny Ortega's dog, Manly "Little Pickles" Ortega . </Li> <Li> Countess is Roger Elliston's well - trained dog who appears in Sharpay's Fabulous Adventure . Countess meets another dog called Boi and they fall in love with each other, but their owners initially fail to see their affections . </Li> <Li> Lupe, Tiffany and Dena are Sharpay's friends in Sharpay's Fabulous Adventure who help her to show her father that she's determined to take an offer for Broadway . They are portrayed by Alessandra Cannito, Lauren Collins and Shadia Ali, respectively . </Li> <Li> Jerry Taylor is a famous Broadway producer who offers Sharpay's dog, Boi, the chance to star in his latest show . He is portrayed by Pat Mastroianni in Sharpay's Fabulous Adventure . </Li> <Li> Gill Samms is a producer of Jerry's show . He is portrayed by Alec Mapa in Sharpay's Fabulous Adventure . </Li> <Li> Neal Roberts is another producer of Jerry's show . He is portrayed by Jack Plotnick in Sharpay's Fabulous Adventure . </Li> </Ul> <Li> Jackie, Lea, and Emma are Sharpay Evans' friends, sometimes called the "Sharpettes". The girls are sometimes collectively known as the Sharpettes, as they often act as back - up singers and dancers for Sharpay, but are never referred to as such in the film series . It is apparent that they do not attend East High School and spend the majority of their time with Sharpay during the summer at her family's country club, Lava Springs . They seem to be equally as pampered as Sharpay, but always follow her every order . Jackie, Lea, and Emma are only portrayed in High School Musical 2, by Tanya Chisholm, Kelli Baker, and McCall Clark, respectively . Baker had a role as a cheerleader and dancer in the first film . </Li>

Who sang as gabriella in high school musical