MISSION VIEJO – The naysayers warned Karen Bishop her idea to teach students in a one-on-one learning environment would never work. Three campuses and 25 years later, Bishop said she saw the vision and made it a reality.

She worked for 13 years in public education, and watched students in traditional classrooms, continuation school and independent study struggle to learn in large groups or on their own.

"The students weren't getting enough instruction," Bishop, 60, of San Diego, said of independent study. "They'd show up, turn in their homework, and someone would give them another homework assignment but nobody would really teach them anything."

She founded Futures High School – now called Halstrom High School – in Oceanside in 1985, citing research from the University of Chicago that showed students who learn one-on-one achieve a 98 percent learning rate.

In 1990 Bishop opened in Mission Viejo – her only school in Orange County. She later opened in San Diego and moved the Oceanside location to Vista, an adjacent city. Courses are also offered online.

Bishop said students come to Halstrom for many reasons, some are trying to be professional athletes or actors, others are bullied at school, bored with traditional learning environments, going through cancer treatments or have mild learning disabilities.

"Gossip Girl" actress Blake Lively, figure skater Sasha Cohen and pro skateboarder Ryan Sheckler are former students.

Tuition runs $865 per semester per course and full-time students average four to five courses per semester. The school is certified by the Western Association of Schools and Colleges and approved by the NCAA for athletics.

Students can enroll at any time during the year, and their course work begins from the day they do so.

Teachers are either trained educators or working professionals, and all schools are located in office buildings so students interact with professional adults, Bishop said.

Students have some group work, but mainly rotate amongst teachers to learn subjects including mathematics, foreign languages and science lab.

"It's easier to ask questions," said Ainsley Kosinski, 17, of Tustin. "Sometimes when you're in class people ask questions you already to. You don't have to worry about that. It's more personalized."

"I have better grades," added Isha Dhillon, 18, of Mission Viejo. "I can focus better and there are no distractions in class."