Many people are skeptical that online education offers the same student-teacher interaction as traditional bricks-and-mortar schooling.

Others, including Xie Kan, a teacher of TOEFL testing skills via the Internet, see new technology as a way to optimize the learning experience.

He cites 100.com, a teaching site for Internet-based education, as a way to give immediate feedback to students' questions.

"100.com invented some virtual tools to boost this kind of interaction," Xie said.

He's able to ask a question of students who will be sent multiple-choice answers to their computer screens. Their replies are correlated and Xie uses that information to improve and sharpen his lessons.

Xie said it isn't possible to get such accurate feedback from a traditional classroom setting. He taught for eight years at the Hangzhou branch of the New Oriental Education & Technology Group.

In a regular online lesson, students can see the teacher via live video. The teacher cannot see the students, nor can they see each other. This allows more-shy students to take the initiative and answer questions, 31 year-old Xie said.

"Students in online sessions are more eager to engage in interaction and are not afraid to talk because they cannot be seen by others," he said.

Xie, who quit his job at the New Oriental group in 2013, became one of the first freelance teachers at 100.com in February. His full-time job is at a middle school in Hangzhou, the capital of Zhejiang province.

Free TOEFL lessons were begun by 100.com on April 22 as a way for the company to promote itself. The pay is not that high, Xie said.

"I don't mind the current low payment, because I'm eyeing the future and I hope to establish a large group of paying students," Xie said.

If he can find enough students willing to pay for online education, he will make it a full-time job, he said.

YY.com, 100.com's parent, said as many as 127 teachers earned more than 10,000 yuan ($1,618) a month in 2013 from offering the live video service on its platform.