Ulysses F. Olsen High is a school in the series. It is the high school where the main characters all attend.
Students [ ]
Arlene Bluth, a senior and Liz's rival for valedictorian
Jerry Cifarelli, he and Liz date for a while
Maggie McMahon, she's in a relationship with Rick
Rick Surmacz, he's also in a relationship with Maggie
Kyle Valenti, son of Sheriff Valenti
Lucinda Baker, she keeps a website that "ranks the kissing technique of every guy in school"
 Tish Okabe, Isabel's friend
Stacey Scheinin, head cheerleader and rivals with Isabel
Corrine Williams, she's the resident party thrower 
Nikolas Branson, he and Isabel date for a while Craig Cachopo
Doug Highsinger, he dances with Stacey at a party
Faculty [ ]
history teacher; Liz is in her class  Ms. Hardy,
  biology teacher; Max and Liz are lab partners in her class  Ms. Markham,
English teacher; Isobel, Maria, and Arlene are in her class  Ms. Shaffer,  school principal, her car ended up on the roof of the gym junior year because of Isabel 
Trivia [ ]
Guffman High is a rival school.
 The cheerleader uniforms are green and black.
 In the German book translations, Ms. Shaffer is split into two characters: Ms. Shaffer and Mr. Shaffer. 
Adaptations [ ]
In the 1999
television series, the high school is renamed Roswell West Roswell High School.
In the 2019
television series, the high school is renamed Roswell, New Mexico New Roswell High School.
References [ ]
↑ 1.0 1.1
The Wild One, chapter 11: "Yeah, Isabel was good in math. But she was a junior, and Liz was a senior."
The Outsider, chapter 3, Liz speaking to Max: "Should I start with the fact that the UFO crash supposedly happened more than fifty years ago — and you’re only a senior in high school?"
The Seeker, chapter 3: “Hey, I’m still a junior,” Maria answered. “I have time. I’m not an old woman like you.”
The Watcher, chapter 12, described by Alex's father: "Senior in high school and he has no idea what he wants to do with his life."
The Outsider, chapter 4: "Not that there was any real doubt, but Isabel was a junior, and usually the homecoming queen was a senior."
↑ Book 4,
The Watcher, chapter 5, Maria (a junior) asks Michael what it's like being a senior: “Um, yeah. I mean, are the classes a lot harder when you’re a senior? Should I be worried?”
↑ 7.0 7.1
. The Watcher
The Outsider, chapter 8.
The Outsider, chapter 5.
The Wild One.
The Seeker, chapter 11.
The Outsider, chapter 8 and chapter 15.
The Wild One, chapter 1: “You guys don’t know the stuff she’s pulled,” Max said. “Remember last year when Ms. Shaffer’s car ended up on the roof of the gym?” “Yeah!” Alex cried. “That was great!” “That was Isabel,” Max said, frowning.
The Wild One, chapter 1.
↑ Book 5,
The Intruder, chapter 2. "She was wearing a short skirt - green and black," Adam answered. Isabel, Michael though. Isabel in her cheerleading outfit.
↑ The German wiki entry for