Westfield High is a public high school attended by Violet upon her family's move to Los Angeles. Other known students (past and present) are Leah, Becca (portrayed by Christian Serratos), Abby (portrayed by Bianca Lawson), and Tate.
A Memorial plaque honoring the students who died in the shooting now hangs in the school. It states:
In Memory of Our Fallen Brothers and Sisters
Presented by the Westfield High School
Class of 1994
The "Westfield Wolverines" are the actual high school football team of Westfield Academy in Westfield, NY.
The "shooting victims" are actual people who work on "American Horror Story" and is an in-joke among crew members: Jay Cannavo is the AHS production assistant, Luke Maxcy is the Director's Guild of America Trainee working on AHS, Josh Sathre is production secretary for AHS, Mark Finstein is a set decorator, etc.
Only one cast member playing a high school student is actually high school age: Taissa Farmiga, age 17. Bianca Lawson is 32, Evan and Allessandra are both 24, and Brad is 25.
The Westfield library is a partial reconstruction of the Columbine library. 
The design of the "Westfield Wolverines" mascot is from Dave Turton, Designer's Website. The font of the school's logo is possibly based on the logo of Westfield, Virginia, as well.
Westfield High in Chantilly, Virginia, was the high school that Virginia Tech shooter Seung-Hui Cho graduated from. Seung-Hui Cho killed 32 people and wounded 25 others before committing suicide at Virginia Tech in the deadliest shooting incident by a single gunman in U.S. history.
Westfield High, VA, was also part of an extensive heroin ring.