Changes in the exam structure and education reforms have led to a surge of students joining cram schools which mainly cater to senior secondary students who are tackling public exams.
This has helped private tutoring schools like Modern Education, King's Glory and Beacon College to flourish.
A South China Morning Post article described how Fred Chan Yiu-fai, a secondary school economics teacher, set up his own private tuition school, Champagne Education, several years ago and claims to be earning "millions". According to the article, Modern Education was worth HK$150 million on the stock market last year.
But the popularity of tutoring centres has been steadily growing for some time.
Even before the education reforms, the pressure to excel in exams to guarantee a university place has seen students increasingly turn to cram schools and mock papers.
Last June, Britain's The Independent newspaper published an article, "Exam-obsessed Hong Kong makes celebrity tutors rich". It blamed the exam-oriented education system for the city's cram-school culture.
"Tutor King" Richard Eng, who co-founded Beacon College, says that tutorial school enrolments can reach up to 100,000 students every year. This is due to tough competition for a university education, which is now considered a basic necessity to support yourself in an affluent society like Hong Kong.
As the HKDSE system is implemented, and secondary school students get just one chance at a public exam to enter university, tutoring centres have become even more popular. Some worry that this trend could undermine mainstream education, as cram centres will be seen as replacements for normal schooling.
But even as students are dozing off in class after late-night classes the day before, it also may be the case that teachers are just not trying hard enough to arouse student interest, and blame the popularity of cram schools rather than their own shortcomings.