For many of Chow's students, the advertisements may be the closest they'll ever get to him.
The 30-year-old teaches English grammar to thousands of secondary school pupils, who attend his after-school lessons or watch video replays of them at Modern Education's 14 branches. Chow is a celebrity tutor in Hong Kong, where there's big money to be made offering extracurricular lessons to parents desperately seeking an edge for their children preparing for the city's intense public entrance exam for university.
Global student rankings out last week highlighted the city's cutthroat academic atmosphere. Hong Kong teens, along with Shanghai, Singapore, South Korea and Japan, dominated the list compiled by the Organization for Economic Cooperation and Development. American students showed little improvement and failed to reach the top 20 in math, science or reading.
Students in East Asian societies have long relied on so-called "cram schools," but Hong Kong has taken them to a new level in recent years, with the majority of students attending the city's nearly 1,000 tutorial centres. Academies use brash marketing, dressing their tutors in miniskirts and high heels or leather jackets to make them look like pop stars. Advertisements for these "tutor kings" and "tutor queens," as they are known in Cantonese, are splashed on giant roadside billboards, on the sides of shopping malls and on newspaper front pages.
Many promise students they can help them ace the entrance exam.
"Basically the examination is just a game. When there's a game there must be both winners and losers. They have to know the tricks on how to win the game," said Chow. "We are trying to get them the shortcuts, the fast track to the answers."
Chow and others promise, for example, that they will help students learn keywords that many believe examiners award points for when used in written answers.
Hong Kong's tutorial industry is worth $260 million a year, according to a report by market research firm Synovate commissioned by Modern Education's parent company, which went public in 2011 and is one of a handful dominating the market.
The industry has made some tutors extremely wealthy. One of the best known, Richard Eng, is famous for his love of Lamborghinis and Louis Vuitton. He's credited with kicking off the transformation of Hong Kong's tutoring industry starting around 1996 when he had the inspiration to market himself like a performer.
While Chow won't say how much he earns, the top tutors can be paid many times what a public school teacher earns. Modern Education's highest paid tutor earns at least 16 million Hong Kong dollars ($2 million) a year, according to its parent company's latest annual report. The second highest earned $1.9 million and third highest made $1 million. Their identities were not disclosed.
The salary figures may not include marketing costs, which the schools share with the tutors, who work as contractors. Chow says he spends thousands of dollars printing glossy exercise books he gives free to students. He split the cost of the bus ads, which cost HK$15,000 per bus, with Modern Education.
Another tutor, Karson Oten Fan Karno, moonlights as a rapper and is popularly known by the name K. Oten. Lung Siu Kwan was a public school teacher who released an album of pop songs and was then recruited as a Chinese tutor by the King's Glory Education chain.
Facebook profiles, YouTube videos and other social media are also part of the aggressive marketing tactics.
"Every night after they finish their classes I will send them messages through WeChat," a popular smartphone app, said Chow. After all, he said, "the most powerful tool is word of mouth within students."
To many students, the glamorized images of Hong Kong's celebrity tutors has also, paradoxically, made their regular teachers appear less credible.
"It's like he has the teaching skills whereas I don't know if my teachers have the same qualification," said Amy Wong, a 16-year-old who was one of about 60 pupils taking Chow's weekly class on a recent night at branch in a suburban shopping mall.
Some students watched the lesson through a glass wall — regulations limit classrooms to 45 pupils so cram schools get around this by subdividing the room.
Others who couldn't make his live lesson watched a replay at other branches around the city. But the most they saw of Chow was a close-up of his hand using a pen to complete English idioms in a workbook while explaining almost exclusively in Cantonese. Questions from students are discouraged. Modern Education, which has 428,000 course enrollments, charges up to $74 for four of Chow's one-hour classes each month.
Nearly three quarters of Hong Kong students attend tutorial classes, according to a survey by Mark Bray, director of Hong Kong University's Comparative Education Research Center.
With the rate so high, others "that don't go to tutoring begin to feel nervous," Bray said. "The companies like that, the companies like nervous people and they trade on anxiety."
Pressure is also rising after Hong Kong's education authorities in 2012 reduced the number of university entrance exams to one from two. The move was designed to reduce student anxiety but Bray said it had the opposite effect, turning it into a "make or break" test.
He said Hong Kong's tutoring companies are using technology to lower costs to students, but that doesn't necessarily mean students are learning as much as they would if they had one-on-one tutoring.
"It's a bit like the fast food Industry. You can go to a fancy restaurant and have white table cloth and beautiful music in the background or you can go to fast food," Bray said. "You can still fill your stomach but maybe the quality is different."
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