After Ben Hathaway's father was called to active duty in the Army National Guard, the 15-year-old had to help his family tend the 130 head of cattle on their 345-acre farm in Leoma, Tenn. Traditional school burned through too many daylight hours, so Hathaway started taking online classes through Lutheran High School of Orange County, some 1,750 miles away.
"Mom was having trouble running the farm by herself," Hathaway, who is taking algebra and world history online, said in a phone interview. "You can schedule everything on your own time. You don't have to sit for six hours a day -- you can do some work, go eat, play a little on the computer and come back later and do it."
Hathaway, who hopes to be a novelist, is among 1 million kindergarten through high school student enrollments in virtual schooling across the nation, according to the North American Council for Online Learning, a nonprofit organization for administrators, teachers and others involved in online schooling.
Enrollment, counted as the total number of seats in all online classes, not the number of students, has grown more than 20 times in seven years, and the group expects the numbers to continue to jump 30% annually.
To deal with the growth, the University of California is launching an extensive effort to make sure applicants' online high school courses are on par with traditional classroom instruction.
Nearly half the states offer public school classes online, and last year Michigan became the first in the nation to require students to take an online course to graduate from high school. In California, a state senator introduced a bill last week to allow public high school students to take online classes without depriving schools of the state funding they receive for attendance.
Online learning "is going to reinvent high school in the United States," said Ken Ellwein, executive director of Lutheran High School of Orange County, which created its online school last year.
"To keep technology away from kids while they're going to school, when they have it in every other part of their lives -- it just doesn't make sense."
But other educators urged caution, noting that teacher-student interaction is irreplaceable.
"In the classroom, I can see from a child's eyes or body language, 'Boy, I better slow down and go back over this,' " said Gerry Wheeler, a former physics teacher who is executive director of the National Science Teachers Assn. in Arlington, Va.
The U.S. Department of Education plans to release a study about the prevalence of online schooling later this year. But one survey the department completed nearly five years ago found that 36% of school districts in the nation had students enrolled in virtual school, mostly high school students.
"We've certainly seen an increase," said Tim Magner, director of the department's Office of Educational Technology. "It's growing fast."
He said students often enroll in online classes to take Advanced Placement or other specialty courses not available in their local schools. Making up a failed class or adding courses that would not otherwise fit in a student's schedule are other top reasons, he said.
Online schools are also popular with home-schooled children, with students who are devoting large blocks of time to such activities as ballet, acting or tennis, as well as students who don't enjoy a traditional school atmosphere or who need to work.
"It's not a matter of intellect or aptitude. The most important factor would be the [student's] desire," said Patty Young, director of Orange Lutheran Online. "Students today really want a customized education. Why should school be confined to an old-style box with a daily schedule?"
Paul Riscalla, 17, a senior at Orange Lutheran who lives in Orange, splits his time between online classes and the traditional school so he can work 40 hours a week at two jobs and play drums in a rock band.
"It was a way for me to have more time outside school, because I have a lot of stuff going on," he said.
Other parts of the nation have a head start on virtual schooling, with 24 states running online schools. Nearly 30,000 students take classes at Florida Virtual School, which has a $43-million annual budget and, at nearly a decade old, is the nation's oldest and largest statewide online public school.
"Many states are realizing the world is moving in this direction, and we need to prepare kids to be able to work and exist in this type of environment," said Julie Young, co-founder of the Florida school.
In California, online schools are run through private schools such as Orange Lutheran, as well as public schools, universities and businesses.