Analyses | Education and human resources | 2017-02-15

Science education in Hong Kong: The 2015 PISA report and educational reforms

Science, Technology, Engineering, and Mathematics (STEM) education has become a much-discussed topic in Hong Kong. On January 18, 2017, the Chief Executive of Hong Kong declared in his 2017 Policy Address that the Education Bureau (EDB) will provide each public secondary school with a one-off subsidy of $200,000 to facilitate the implementation of school-based programmes related to STEM education.[1]

On December 6, 2016, the Organisation for Economic Co-operation and Development (OECD) published the results from the 2015 Programme for International Student Assessment (PISA). PISA assesses the performance of 15-year old students in mathematics, science and reading across 34 OECD countries and 31 partner countries and regions, including Hong Kong. The 2015 PISA report revealed that while Hong Kong ranked second behind Singapore in mathematics and reading, the region dropped from second to ninth place in mean science score as compared to the previous PISA examination in 2012.[2] This result could be significant considering the fact that the mean science score in Hong Kong had been increasing steadily from 2003 to 2012 before abruptly dropping in 2015.[3]

The mean science score for Hong Kong students in 2015 was 523, a 19-point drop from the mean score in 2006. This exceeds the average decrease in science score across all OECD countries from 2006 to 2015 by 12 points. Moreover, between 2006 and 2015, the number of “high achievers” in science on the PISA test (defined as the number of students with a score higher than 633.33 points) in Hong Kong decreased by 8.6%. This was the largest decrease in “high achievers” in science of any country or region from 2006 to 2015.

Performance in science and student attitudes towards science in Hong Kong

It is likely that many factors contributed to the decrease in science scores in Hong Kong. Two possible factors that were measured by the PISA test were students’ levels of intrinsic and extrinsic motivation to learn science. Based on the enjoyment of science index, which measures intrinsic motivation to learn science through responses to statements affirming the level of satisfaction in various science activities, Hong Kong students enjoyed science to a lesser degree in 2015 as compared to 2006. By contrast, student enjoyment of science increased among all OECD countries within that time frame.

As the OECD points out, enjoyment of science affects students’ willingness to spend time and effort in science-related activities, the choice of electives, students’ self-image, and the type of careers students choose to pursue. In Hong Kong, students ranked in the top quarter of the enjoyment of science index also had a mean science score of 554, while those in the bottom quarter scored 493. Thus, it may be worthwhile for the EDB to explore some policy initiatives that can enhance enjoyment of science among local students.

The PISA report did not explore the precise nature of the interaction between performance and enjoyment of science, so it is possible that students enjoy science because they perform well, and vice versa. It should also be noted that the enjoyment of science index is still much higher in Hong Kong than the OECD average, notwithstanding the drop in 2015.

While Hong Kong students scored lower on the enjoyment of science index in 2015 than in 2006, this was not the case with regards to instrumental motivation to learn science, defined by PISA as “the drive to learn science because it is perceived to be useful to future studies and careers”. According to the instrumental motivation to learn science index, measured by student responses to questionnaires regarding their perceptions of the usefulness of science, more Hong Kong students were extrinsically motivated to learn science in 2015. The increase was lower than the OECD average, however.

Intrinsic motivation to learn science vs. extrinsic motivation to learn science

Hong Kong students in the top quarter of the instrumental motivation to learn science index scored 29 points higher on the PISA than students in the bottom quarter, as compared to the 62 point disparity for the bottom and top quartiles of the enjoyment of science index. According to the OECD, based on the 2015 PISA results, “The association between instrumental motivation and performance is weaker than the association between intrinsic motivation and performance…on average across OECD countries”.[9] This could be the case in Hong Kong as well, although the OECD did not make this specific conclusion.

To ensure that local students are prepared for the new opportunities of the technological era, it may be helpful for the EDB to focus on improving academic proficiency and increasing the level of interest in science. At the same time, the EDB may consider exploring other potential factors behind the drop in performance, such as the level of stress on local students, the importance of science in the senior secondary curriculum and university admissions, as well as the perceptions of science-related professions in local society.

PISA results show that countries with more students engaging in science activities outside of school often saw increases in students’ intrinsic motivation to learn science.[10] To that end, the EDB’s Report on the Promotion of STEM education in December 2016 supported further promotion of extracurricular science activities such as science exhibitions, symposiums and competitions in Hong Kong.[11] The Report also recommended that schools nominate students with special talent in STEM areas to apply for local and overseas scholarships to facilitate specialisation in STEM-related studies, while noting that providing more hands-on learning activities for students in the classroom could cultivate their interest in science. If properly implemented, these efforts could lead to lasting improvements in students’ enjoyment of and performance in science.

Hong Kong schools offer strong equity in education

Notwithstanding the troubling statistics, the PISA report did include many encouraging signs for science education in Hong Kong. According to the OECD, in 2015, the percentage of variation in science performance explained by students’ socio-economic status in Hong Kong is only 5%, while the OECD average is 13%. And while 62.9% of the variation in science performance in 2015 between schools across all OECD countries can be explained by differences in the schools’ and students’ socioeconomic status, the percentage in Hong Kong is significantly lower, at 40.9%. Finally, 90.6% of local students achieved the baseline level of science proficiency in 2015, which is the third-highest percentage in the world.

These figures imply that Hong Kong continues to be a world leader in providing equity in science education. Nonetheless, the drop in the number of high achievers in science and the decrease in science score is worrisome. According to Dr. Eric Liu Sai-lok, Principal of the Institute of Vocational Education, if students do not improve their ability in science, this will have a far-reaching impact on Hong Kong’s innovation and technology development.[12] As an example, several local employers in the technology sector have complained about the difficulty in finding talented local students, according to the lawmaker Charles Mok Nai-kwong.

The impact of educational reforms on science elective selection

Relatively few Hong Kong students took multiple science electives (defined as Biology, Chemistry, Physics, Integrated Science, and Combined Science) in 2015.[13] In 2012, 26% of all Hong Kong Diploma of Secondary Education (HKDSE) candidates took one science subject, 25% took two science subjects and slightly over 5% took three science subjects.[14] In 2015, while the percentage of students taking one science subject had increased to 30%, the percentage taking two subjects dropped to 21.6% and the percentage taking three dropped to 3.6%.[15]

Professor Esther Ho Sui-chu, Director of the Centre for International Student Assessment, believes that since many high-performing students no longer choose to take three science subjects, their scope of science knowledge has become significantly less well-rounded. As such, high-performing local students may feel less confident in answering questions on comprehensive assessments such as the PISA that cover all the major domains of science. It is difficult to evaluate this assertion, however, because no data is available to show the extent to which students taking Biology, Chemistry or Physics at the Form Four level may have performed better on the PISA test relative to students without any science electives.

To understand why fewer students in Hong Kong are taking multiple science electives, it is necessary to overview developments in the education system. On January 5, 2017, the Academy of Sciences of Hong Kong released a report entitled “Science, Technology and Mathematics Education in the development of the Innovation and Technology Ecosystem of Hong Kong”. The Academy interviewed 154 secondary school principals to assess the impacts of the 2012 educational reforms which created the HKDSE system and abolished the Hong Kong Certificate of Education Examination (HKCEE) and the Hong Kong Advanced Level Examination (HKALE), in which students were streamed into Arts and Science tracks.

Most Science stream HKCEE students took three science electives, and most Science stream HKALE students took at least two. Approximately 40% of all Hong Kong students were in the Science stream. After 2012, however, streaming was abolished and all senior secondary students are required to take four core subjects - English, Chinese, Mathematics and Liberal Studies. Students must score a Level 3 on the Chinese and English exams and a Level 2 on Liberal Studies and Mathematics to be admitted to a University Grants Committee (UGC) funded school under the Joint University Programmes Admissions System (JUPAS).

It is interesting to note that the addition of Liberal Studies and Mathematics as core subjects did not lead to improvements in PISA reading and mathematics scores; in fact, the mean score for reading was 18 points lower in 2015 than in 2012, and 11 points lower than in 2006.[16] The mean mathematics score was also 13 points lower in 2015 than in 2012, although it was one point higher than the mean score in 2006.

Core subjects are overemphasised at the expense of electives

The number of students taking three electives has steadily declined under the HKDSE. In 2015, only 16% of students took three electives, compared to 27% of students in 2012. According to the Academy of Sciences, this is due to university admissions procedures and the tendency for schools to overemphasise instruction on the four “core subjects”.

Many programmes offered at the UCG-funded universities in Hong Kong use the “Four core subjects and two electives” (4C + 2X) or the “Four core subjects and one elective” (4C + 1X) system as general selection principles. The remainder uses variants of the “Best Five subject” system as selection principles. Under the 4C + 2X or 4C + 1X system, only the four core subjects and the best one or two electives are assessed. Students have little incentive to take three electives, as not more than two electives will be assessed and devoting significant time to a third elective may diminish the test scores for the four core courses.

By contrast, the Best Five system assesses the top five scores from all tested subjects. While the Best Five system could allow for students to be assessed based on two core subjects and three electives, in practice the Academy reports that most students believe that securing good marks in the four core subjects and no more than two electives is still the most “efficient” way to prepare for university admission. This is especially the case because few university programmes clearly state a subject preference in assessing applications and many programmes do not award bonus marks for students with three electives.

Most school principals indicated in the Academy’s survey that their teachers prioritised teaching time for the four core subjects. Fifty-five percent of the principals stated that the four core subjects occupied more than 60% of normal teaching time, higher than the EDB’s recommended percentage of 45-55%. This has left inadequate teaching time for elective subjects. Indeed, only 62% of interviewed principals stated that their schools allow students to take three electives, and 38% of principals permit students to take only two electives.

The negative consequences of fewer students taking science electives

The Academy argues that the combination of university admissions policies, the heavy emphasis on the core subjects, and the lack of elective offerings has made the core subjects the “high stakes” subjects of the HKDSE. Moreover, three of the four core subjects are either language or language-centric subjects (English, Chinese and Liberal Studies) while only one is more numbers-oriented (Mathematics). Since the core subjects are highly significant in both the 4C + 2X and the Best Five university admissions systems, science students who are not as strong in language skills may be disadvantaged. These students could also be discouraged from taking multiple science electives to allocate more study time for the core subjects.

With so few students taking science electives, many students are now inadequately prepared to study science in university. The University of Hong Kong’s (HKU) Dean of Science, Professor Pauline Chiu, stated that HKU was forced to introduce foundation courses for new students to catch up on mathematics and science fundamentals after realising that students are now weaker in science knowledge after the HKDSE was introduced.[19] Yet as the Academy report notes, it is difficult to condense two or more years of studies at the senior secondary level to one year in university or post-secondary vocational programmes.

To resolve these issues, the Academy has suggested “trimming the core subject requirement” to balance science and language education to make room for more elective subjects, particularly science subjects. This could be done by reducing the breadth and depth of the core subjects. Eighty-nine percent of the survey respondents also supported reviewing Liberal Studies as a core course and 71% suggested cutting core subjects from four to three or 3.5.

The Academy also recommended that universities revise their admissions criteria so that science programmes assess HKDSE results based on relevant subjects instead of overly weighing the core subjects. For example, bonus points could be awarded for taking three electives, or science subjects could be weighed more heavily than non-science related subjects. However, it may be difficult for universities to make these changes while maintaining their intake quotas. Wong Hak-lim, Vice Chairman of the Professional Teachers’ Union, believes that science faculties have had to lower requirements to attract students and compensate for the decreasing number of students taking multiple science electives.

How can the admissions policies at local universities be reformed?

An analysis of the admissions policies at HKU, the Hong Kong University of Science and Technology (HKUST), and the Chinese University of Hong Kong (CUHK) reveal how programmes can encourage more students to take science electives. At HKU, the three largest science-related programmes by intake are the Bachelor of Engineering, the Bachelor of Science and the Bachelor of Medicine and Surgery. Only the Bachelor of Science awards bonus points for students with three electives and weighs science-related subjects more heavily than other subjects. There is little incentive in the admissions process for applicants to take multiple science electives for the Bachelor of Engineering or the Bachelor of Medicine and Surgery.

A similar policy is present at HKUST. There, the Bachelor of Science considers science with the same weight as Chinese or Liberal Studies. Additional electives are only considered in the event of a tiebreaker. Thus, there is minimal incentive for students to devote extra study time on science subjects or to take multiple science electives. As for the Bachelor of Engineering, while the best science elective is weighed with a factor of 2, additional science electives are not given extra weight. So while applicants are awarded bonus points for taking additional electives, there is no advantage in taking extra science electives specifically.

By contrast, several science-related programmes at CUHK provide specific advantages for students with multiple science electives. The Bachelor of Engineering, Bachelor of Science, and Bachelor of Medicine and Bachelor of Surgery programmes all award bonus points for additional electives, and in the case of the Bachelor of Medicine and Bachelor of Surgery taking three electives is essentially a prerequisite.[22] Moreover, all three programmes prefer students that take a science, advanced mathematics or technology-related subject as their second elective, in addition to the mandatory science elective. Science subjects are also weighed more heavily by the Bachelor of Engineering and Bachelor of Science programmes.

In sum, there are several ways for educational institutions to encourage students to take more science electives without adjusting minimum standards and restricting the size of the applicant pool. These include weighing science subjects more heavily than other subjects, giving bonus points for students with three electives, and stating a preference for students who take a science subject as their second or third elective.[24] Of course, there are valid concerns about the need to attract applicants given the decreasing number of students taking multiple science electives. Ideally, the HKDSE would be reformed simultaneously to encourage students to take more electives without adding to their workload.


This article has discussed some of the potential factors behind the decrease in PISA science scores, but it is very likely that other factors are also in play that were not covered or not measured by the PISA report. There is also no data comparing the performance of students in Hong Kong taking no science subjects with students taking science subjects at the Form Four level. It is difficult to explain the significance of factors such as changes in intrinsic and extrinsic motivation to learn science or the decrease in the number of students taking multiple science electives on science performance beyond the PISA test. Finally, although Mathematics and Liberal Studies were added as core courses in the HKDSE system, PISA scores in mathematics and reading surprisingly fell in Hong Kong from 2012 to 2015, and in the case of reading the mean score was also lower in 2015 than the mean score in 2006.

Thus, it is possible that other factors not discussed in this article, such as exam stress and parents’ expectations, have negatively affected education in Hong Kong across all subject areas. It may not be possible to resolve these underlying issues by modifying the HKDSE system or by encouraging students to take more science electives. The EDB could consider taking a holistic approach and analysing all the factors involved in the apparent decrease in science performance and the level of interest in learning science when formulating policy.

Significant developments in science, technology and economics have taken place in recent years. The global educational trend has been to equip students with the capability to confront new opportunities and challenges presented by these developments. Whether or not any specific measures are taken to improve Hong Kong’s performance on the next PISA test, the Government may consider further increasing the awareness among educators, parents and students of the growing importance of science and technology in society.

1 Leung Chun-ying, The 2017 Policy Address,
2 Kinling Lo, Hong Kong slips to new low in international ranking for student performance in science, South China Morning Post, December 6, 2016,
3 PISA 2003: Executive Summary, OECD,
4 PISA 2015 Results (Volume 1): Excellence and Equity in Education, OECD, December 6, 2016,
5 PISA 2012 Results in Focus, OECD, December 3, 2013,
6 Executive Summary: PISA 2006, OECD, December 4, 2007,
7 PISA 2015 Results (Volume 1): Excellence and Equity in Education, OECD, December 6, 2016,
8 PISA 2015 Results (Volume 1): Excellence and Equity in Education, OECD, December 6, 2016,
9 PISA 2015 Results (Volume 1): Excellence and Equity in Education, OECD, December 6, 2016,
10 PISA 2015 Results (Volume 1): Excellence and Equity in Education, OECD, December 6, 2016,
11 Report on Promotion of STEM Education: Unleashing Potential in Innovation, Education Bureau, December 2016,
12 Shirley Zhao and Peace Chiu, Fewer Hong Kong school pupils opt for science subjects, endangering government bid to boost technology sector, South China Morning Post, April 21, 2016,
13 At the time of writing the PISA, most Hong Kong students had only completed one semester of Form Four education. It is unclear exactly how much of an impact one semester of science elective instruction could have had on the PISA test performance, since the material that was taught for this one semester probably varied from school to school. The quality of science education prior to Form Four could have also affected the level of performance.
14 Science, Technology and Mathematics Education in the development of the innovation and technology ecosystem of Hong Kong, The Academy of Sciences of Hong Kong, December 2016,
15 Science, Technology and Mathematics Education in the development of the innovation and technology ecosystem of Hong Kong, The Academy of Sciences of Hong Kong, December 2016,
16 PISA 2012 Results in Focus, OECD, December 3, 2013,
17 PISA 2015 Results (Volume 1): Excellence and Equity in Education, OECD, December 6, 2016,
18 Science, Technology and Mathematics Education in the development of the innovation and technology ecosystem of Hong Kong, The Academy of Sciences of Hong Kong, December 2016,
19 Shirley Zhao and Peace Chiu, Fewer Hong Kong school pupils opt for science subjects, endangering government bid to boost technology sector, South China Morning Post, April 21, 2016,
20 2017 Programme Admissions Information, The University of Hong Kong,
21 JUPAS Applicants: Undergraduate Admissions, The Hong Kong University of Science and Technology,
22 Admission Notes: Faculty of Medicine, The Chinese University of Hong Kong,
23 Programme Requirements, The Chinese University of Hong Kong,
24 It can be argued that these reforms would unfairly disadvantage students who are unable to take more than one science subject. Since many schools do not allow students to take three electives, this is a legitimate concern that cannot be resolved solely by revising selection principles.