iNACOL acknowledges that states need to do a better job overseeing online schools.

More schoolchildren than ever are taking their classes online, using technology to avoid long commutes to school, add courses they wouldn’t otherwise be able to take—and save their school districts money.

But as states pour money into virtual classrooms, with an estimated 200,000 virtual K-12 students in 40 states from Washington to Wisconsin, educators are raising questions about virtual learning. States are taking halting steps to increase oversight, but regulation isn’t moving nearly as fast as the virtual school boom.

The virtual learning debate pits traditional education backers, including teachers’ unions, against lawmakers tempted by the promise of cheaper online schools and school-choice advocates who believe private companies will apply cutting-edge technology to education.

Is online education as good as face-to-face teaching?

Virtual learning companies tout a 2009 research review conducted for the U.S. Department of Education that showed K-12 students did as well or better in online learning conditions as in a traditional classroom.

But critics say most studies, including many in that 2009 review, used results from students taking only some—but not all—of their courses online. They also point out wide gaps in state oversight to ensure students, and not their parents or tutors, are actually completing tests and coursework.

For more news on virtual learning, see:

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iNACOL updates its online teaching standards

Still, virtual learning at the K-12 level is booming. For example, one of the nation’s largest for-profit online education providers, Virginia-based K12 Inc., saw its earnings more than double in the first quarter of this year, fueled in large part by a 42-percent enrollment spike.

“Online learning is the future of American education. Precisely because it’s so transforming, it’s threatening to the established institutions,” said Terry Moe, a political scientist at Stanford University who studies the online school boom.

The conflict has boiled over in Colorado, which expects to spend $85 million this year educating some 14,200 students online. The state’s online school industry is growing by double digits a year, bankrolled by a state government that pays private companies to teach students as young as kindergarten entirely via computer with limited oversight.