I always find it funny that these things surprise us. We consistently and quite bitterly complain about the cost of education and the quality of our children’s schools. We spend millions of dollars trying to improve our school systems with varying levels of success. It therefore should come as no surprise to us when the free markets step in and private lessons step up. If you do not satisfy the customer, someone else will.

The industry, sometimes called ‘shadow education’ or private tutoring, seeks to profit from the perceived failure of the school system. It simply realizes that there is good money to be made off the fact that many students leave the classroom feeling insecure about the lessons they have been taught. Private tutors have historically made a living assisting struggling students, but after-school learning rarely hit the mainstream. Good tutors were hard to find, one-on-one sessions were very expensive, and the logistics of getting children to and from the lessons was a nightmare. Hence the only students who used private tutors either had significant learning issues or significant financial resources.

However, the Internet changed all that. With one teacher now able to easily access many students and teach from the comfort of their own home, the economics of education shifted. In fact, private lessons and shadow education have become lucrative businesses, allowing teacher salaries to well exceed that of their public school peers and thus threaten to attract the best and most capable educators.

A recent article in the Wall Street Journal, entitled “The $4 Million Dollar Teacher,” spotlighted such an educator. Kim Ki-hoon earns $4 million a year in South Korea, where approximately 150,000 students benefit from his online classes. While such services are available in every country, in South Korea they have become a significant component of the educational system, helping South Korea become an academic superpower.

Nearly three out of every four South Korean kids participate in the private tutoring market. In 2012, their parents spent more than $17 billion on these services. That is more than the $15 billion spent by Americans on video games that year, according to the NPD Group, a research firm. The results are equally dramatic: Sixty years ago, most South Koreans were illiterate; today, South Korean 15-year-olds rank No. 2 in the world in reading, behind Shanghai. The country now has a 93% high school graduation rate, compared with 77% in the U.S. Over 47% of South Korean 8^th graders were ranked ‘advanced’ compared to 7% in the U.S.

But the price students pay for such excellence goes beyond the $4 charged for each video lesson. Students go to school twice each day, once in their regular classroom and again after school. In addition to the physical and emotional toll, students will eventually realize that there is no need to learn the same thing twice – a form of thinking which will significantly effect public education. Not only will students suffer, but parents who cannot afford private lessons will either pay the hefty price or put their children at a great competitive disadvantage.

As teachers we must be aware of the public vs. private education phenomenon and be aware that shadow education and online learning may very well become worldwide trends. The positive and negative effects on the teaching profession, especially as regards to public education, must be carefully examined. Are we at risk of losing the best and brightest teachers to the allure of a better paying teaching job? Is the importance of the classroom going to become compromised as students do their ‘real learning’ elsewhere? And finally, who is supervising the quality of this industry? Should free market forces decide the cost of education and how children learn?

While great teachers do not measure their wealth solely by teacher salaries, there are lessons to be learned from every trend – lessons which can make us better educators and our schools better schools.