More U.S. schoolchildren than ever are taking classes online, using technology to avoid long commutes, to add courses they otherwise would not be able to take, and to 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, educators are raising questions about online learning. States are taking halting steps to increase oversight, but regulation is not moving as fast as the virtual school boom. Critics point to gaps in state oversight to ensure students–and not their parents or tutors–are actually completing tests and coursework.