Last year, Jennifer Cho took classes in poetics, screenwriting, and AP English. This year, she's taking electives on the Vietnam War and microbiology, all courses that her local high school doesn't offer.

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A growing number of distance learning ventures across the United States are offering high school credit for online courses, expanding students' access and opportunities beyond traditional classrooms.

"A virtual any time, any place learning experience provides a great opportunity for students to learn at their own pace and direction," said John Blair, president and CEO of Class.com, a commercial spin-off of the University of Nebraska that provides virtual courses to high schools.

Kentucky Governor Paul Patton recently announced a deal with Class.com to sell online courses to every high school in the state. Beginning in January, the Kentucky Virtual High School will help boost small, rural schools that cannot attract upper-level math, science, and foreign-language teachers.

With virtual enrollment, schools that lack funds and resources can extend course offerings and provide alternative methods of learning to students with special needs.

The Virtual High School, a collaborative of national high schools that is financed by a five-year, US$7.8 million Department of Education Technology Challenge Grant, offers participating schools NetCourses in exchange for teaching time. Students can explore nontraditional courses from music appreciation to aeronautics, classes that could not otherwise be offered because of low enrollment.

"You won't find a class like 'Scientific and Religious Perspectives on Intelligence' being taught in a regular high school, but here we're given the opportunity," Cho said.

The virtual environment encourages different learning styles. Without in-class teachers, students become self-directed, independent learners. This can give some students better opportunities to learn.

Students who might not otherwise participate in traditional classrooms can engage in email threads and discussions that transcend communication differences.

Enrolling in a Virtual High School class has allowed Kimberly Leigh Clapp, who attends an all-deaf school in Maryland, to participate in class discussions without an interpreter.