Prince William County is adding two Advanced Placement courses to its fast-growing Virtual High School program as part of a state initiative to provide advanced courses to all its students.

The county will offer AP biology and U.S. and Virginia government in the fall, as well as three other new Virtual High School classes: chemistry, Spanish III, and health and physical education. Like all Prince William Virtual High School courses, the classes are available to students outside the county. In addition, home-schooled students are able to take up to two classes in the program each semester.

The online high school program has grown in popularity since it was first offered in summer 2001, coordinator Gina Jones said. About 50 students enrolled that first semester in five courses. This summer, 280 students were enrolled in 16 different courses. Jones said she expects about 120 students in the fall.

Students come to the program for different reasons, she said.

"We have rising freshmen, students who want to work ahead, homebound students, students who are suspended or moving in from other states who want to make up credits," Jones said. "It's really a hybrid."

Most classes meet as a group only once. For chemistry and foreign languages, there are some face-to-face meetings for lab work. In addition, Prince William requires English 11 students enrolled in Virtual High School to meet face-to-face because of the county's research paper requirement.

But for the rest of the subjects, students are mostly on their own, even for health and physical education. In that class, students will take the health component online and go to a community center or a gym for the physical fitness component. A signed time log will be required to fulfill that requirement. Such a program would work well for students who are already involved in extracurricular sports activities, Jones said.

Successful Virtual High School students are self-disciplined and practice good time management, Jones said. Students are expected to spend three to five hours a day on class work, including reading, homework and online discussions, and classes that normally take one school year are compressed into one semester.

Allowing students to work on their own in classes that are smaller than average has proven to be beneficial. The average pass rate is 73 percent, the pass rate for Standards of Learning tests is 81 percent and the student-teacher ratio is 8 to 1.

Teachers are lining up to participate in the program. "We like to say we hire the best and the brightest," Jones said.

Gretchen Henderson, a U.S. and Virginia history teacher at Woodbridge High School, also teaches the course for the Virtual High School. She said she has incorporated some of her online lessons into her traditional classes: Instead of a long lecture on Franklin Delano Roosevelt, she allows students to listen to a recording of his inaugural address. A lecture about westward expansion includes a visit to the National Cowboy Museum's Web site.

"The fact that this course has bells and whistles and gadgets is appealing to some kids," Henderson said. "And it's appealing to me, too."

The success of the county program is one of the reasons Prince William was selected to carry out Gov. Mark R. Warner's Early College Scholars program. The state has budgeted $300,000 to pay tuition and examination fees for students who enroll in long-distance AP courses. The program is intended for students in rural school districts who may not have the same access to AP courses as students in Northern Virginia.

In addition to AP biology and U.S./Virginia government, which will be offered by Prince William teachers, the state will also pay tuition and enrollment fees for students who enroll in distance-learning AP classes in chemistry, biology, Spanish, human geography, English, physics, macro and microeconomics, psychology, calculus and statistics.

Some of those courses will be taught online, while others will be taught through satellite broadcasts, said Greg Weisiger, the state's associate director for teleproductions.