Cornell University associate professor Noliwe M. Rooks worries that online or virtual learning will leave students behind. As she writes in a recent Time column:

Over the past 10 years, public school districts have invested millions of dollars in various types of online and computer-aided learning and instruction programs, yet few are able to show the educational benefit of their expenditures for a majority of students.

Until recently, most traditional public schools didn’t try to show that–much less how–students were benefiting the billions of taxpayer dollars they receive each year. But Larry Cuban, professor emeritus of education at Stanford University and author of Oversold and Underused: Computers in the Classroom, explains why simply plunking computers in public-school classrooms is no miracle cure:

Technology is linked to progress in the American mind and has a rich history in the culture. … [but] no “revolutions” in technology use have occurred in U.S. schools and classrooms. …It is a mistake to assume that if schools just adopt classroom technologies, academic achievement will improve, teaching will change dramatically, and students will be better prepared for the 21st-century workplace. …the bedrock of schooling remains an organizational structure introduced in the mid-19th century… Advances in new technologies have hardly made a dent in this permanent structure. …Until the age-graded school and funding mechanisms change, the use of new technologies for classroom instruction will remain peripheral.

Other experts stress that the transformative power of online education has been occurring from the bottom up for nearly two decades, not from the top down. Commenting on recent federal education reform efforts, Reason magazine senior editor Katherine Mangu-Ward characterized a 10-year, $500 million plan proposed by U.S. Education Secretary Arne Duncan to develop post-secondary online courses as “arriving at the dance 15 years late and an awful lot more than a dollar short” because this is an “area of online education already thriving without federal assistance.”

Online education options have been a boon to students who need specialized services and parents who want individualized instruction. Students in rural areas or those attending schools with limited course offerings, such as languages or advanced placement (AP), also benefit greatly from enhanced learning opportunities.

Evidence also suggests that while online education options aren’t cheap, they’re still less expensive that traditional public schools. The average American public school gets more than $12,000 in per-pupil funding, yet achievement has remained largely the same since the 1970s. In contrast, the cost of educating online education students can be as much as $5,000 lower.

Empirical research about the academic achievement of K-12 students participating in online education is sparse. A recent analysis sponsored by the U.S. Department of Education, however, reviewed more than 1,000 studies comparing online learning with traditional learning. Most of the studies reviewed focused on postsecondary students, and researchers caution about generalizing higher education findings to K-12 education given the smaller sample size. Still researchers acknowledge that their K-12 findings resembled their higher education findings, which concluded that online classes produce stronger average student achievement than traditional classes and promote more time-on-task.

This is an important development since previous research found that the academic performance of high school students taking online courses was at least equivalent to that of students in face-to-face courses.

The reality is online education is a bottom-up approach driven by parents and educators who want customized learning options at a reasonable price. That helps explain why today an estimated 1.5 million students nationwide are taking one or more online courses. Experts predict that by 2014 roughly one out of every five public-school students (about 10 million) will be enrolled in online courses of some kind.

More—and better—customized learning opportunities should be a welcome policy change because it makes affordable opportunities available to students without regard to geographical or financial limitations.