Impacts of a STSE high school biology course on the scientific literacy of Hong Kong students

Hong Kong has consistently ranked among the top in scientific literacy as assessed by the Programme for International Student Assessment (PISA): third in 2000, 2003 and 2009, and second in 2006 where science was the major domain (HKPISA, 2011). Despite these seemingly remarkable performances, doubts are cast on the quality of the curriculum and instruction of science in Hong Kong. Studies found that science classrooms of Hong Kong were dominated by didactic, teacher-centered instruction (Tsang 2004), overemphasizing the acquisition of scientific knowledge over the development of scientific inquiry skills and understandings of the nature of science (NOS) (Cheung 2000). Students were seldom given opportunities to conduct open-ended, independent investigations, while most of the practical work were recipe-type and highly teacher-directed (Yip and Cheung 2004). These observations are consistent with the performances of Hong Kong students in some areas of PISA: relatively good at explaining phenomena scientifically, which pertains more to scientific knowledge, but weak in identifying scientific issues, which is about scientific reasoning and understanding of NOS (HKPISA 2011).

The PISA results suggest that there is room for Hong Kong students to further improve their scientific literacy (SL) through shifting the emphasis of science instruction from scientific knowledge to scientific inquiry and nature of science. However, Hong Kong, as with most Asian communities, has an overly exam-oriented education system, in which preparing students for public examinations is the major goal of schooling (Tsang 2004; Tsui, 2008; Yip and Cheung 2004). Despite that recently public science examinations in Hong Kong have put greater weight on the assessment of scientific inquiry skills and nature of science, they are still heavily loaded with scientific facts and concepts, particularly in the Hong Kong Advanced Level Examination (HKALE). This overly examination-oriented culture, along with other factors, has become the major constraint for science instruction moving towards greater emphasis on scientific inquiry and nature of science in Hong Kong.

Since 2009, a new senior secondary school curriculum has been implemented in Hong Kong, in which the original 2-year study for the Certificate of Education Examination (HKCEE) plus subsequent 2-year study for the Advanced Level Examination (HKALE) were replaced by a 3-year study leading to the Diploma of Secondary Education (HKDSE). The subject curricula at senior secondary also get major revisions. The new science curricula have put much more emphases on scientific inquiry, science-technology-society-environment (STSE) and nature of science (Curriculum Development Council and Hong Kong Examination Authority 2005). These changes in science curricula and public assessments give hope for a substantive transformation of science instruction in Hong Kong.

This study seeks to explore if a STSE approach to science instruction is feasible in Hong Kong schools. That means, the STSE course can, on the one hand, effectively address many important goals of science learning, namely scientific inquiry skills, NOS understandings and STSE awareness, while, on the other hand, meet the heavy demand of scientific knowledge in coping with the Hong Kong public exams.

The research questions of this study are:

How should a STSE biology course be developed so that it not only emphasizes scientific inquiry, nature of science and STSE relationships, but is also as effective as traditional class in the learning of scientific content knowledge?

What are the impacts of this STSE high school biology course, as compared to the traditional class, on the scientific literacy of Hong Kong students in terms of scientific content knowledge, scientific inquiry skills, understandings of nature of science, STSE awareness and attitudes towards science and science learning?

STSE education

STSE education has emerged as a major movement in science education since the 70s and remains one of the key emphases in the science education reforms worldwide nowadays (Pedretti & Nazir 2011). STSE generally refers to the curriculum and instruction that address the connections between science, technology, society and environment, and a comprehensive review of STS education has been made by Aikenhead (2002). Different from traditional curriculum that stresses the mastery of scientific content knowledge, STSE education has a major goal of developing social responsibility in collective decision making on social issues related to science and technology.

Aikenhead (1994) proposes a scheme of Categories of STS Science to classify the diverse STSE practices. Eight categories of STS science are ordered according to their priority given to STSE content: 1. Motivation by STS content, 2. Casual infusion of STS content, 3. purposeful infusion of STS content, 4. Singular discipline through STS content, 5. Science through STS content, 6. Science along with STS content, 7. Infusion of science into STS content, 8. STS content. The proportion of STSE content progressively increases from categories 1 to 8, along with decreasing emphasis of scientific content knowledge. Starting from category 4, the curriculum organization is determined by the STSE content rather than the internal structure of the discipline used by traditional science curriculum. Though it is hard to say which category represents ‘true’ STSE, research shows that students get additional benefits from STSE course in category 3 or above (Aikenhead 1994).

Pedretti and Nazir (2011) reviews 40 years of STSE education and identify six currents of STSE education: application/design, historical, logical reasoning, value-centered, sociocultural, and socio-ecojustice currents. This framework allows the classification of diverse STSE education by its different foci and aims. The Application/design current centers on technology and practical problem solving. The historical current emphasizes understanding science from a historical perspective. The logical reasoning current is mainly about rational decision making for socioscientifc issues (SSIs). The value-centered current, on the other hand, addresses mainly the values and morals when dealing with SSIs. The sociocultural current places great importance on understanding science within a sociocultural context. The last one, socio-ecojustice current, is concerned more with actions than simply understanding.

As for the instructional approach, while traditional science is characterized by direct teaching, demonstration and experiments, STSE instruction usually makes uses of a wide range of interactive learning activities like role-play, discussions, simulations, games, decision making, debates and problem solving. Aikenhead (1994) suggests a general approach to STSE instruction (see Figure 1), in which instruction begins with a social issue, and then related technological and science concepts are drawn in. With the knowledge acquired, the social issues are revisited. This approach can make learning happen in a meaningful context.

As for the learning outcomes of STSE education, Aikenhead (2003) concludes that students in STSE classes, as compared to traditional class, can learn science content equally well or even better, significantly improve their understanding of the interactions among science, technology and society, notably develop their attitudes toward science and science learning, and make modest but significant gains in thinking skills, such as creative thinking, decision making, and application of science content to everyday situations. Nonetheless, the learning outcomes depend largely on a purposeful integration of STSE contents into the curriculum and the use of sound instructional strategies.

Scientific literacy

Scientific literacy (SL) is a major goal of science education in many reform documents, such as Science for All Americans (American Association for the Advancement of Science [AAAS] 1989) and Benchmarks for Science Literacy (AAAS 1993). A detailed analysis and comprehensive review of scientific literacy was made by Roberts (2007), in which two Visions of SL are distinguished. Vision I centers on the perspectives of science and scientists and therefore stresses the learning of scientific knowledge and skills, whereas Vision II centers on the sociocultural perspectives and stresses an understanding of the roles of society, cultures and values. While Vision I is criticized to be narrow, Vision II could not adequately address scientific skills and knowledge. These two Visions of SL, however, can be integrated with Pedretti and Nazir ‘s (2011) currents of STSE education, with the first three currents belonging to Vision I, and the last three Vision II.

Despite that there is “no consensus about the meaning, or even the constituent parts of SL” (Roberts 2007, 735), PISA, in its attempt to make an international comparison of scientific literacy, has constructed an operational definition for scientific literacy (HKPISA 2008): For the purposes of PISA 2006, scientific literacy refers to an individual’s:

Scientific knowledge and use of that knowledge to identify questions, acquire new knowledge, explain scientific phenomena, and draw evidence-based conclusions about science-related issues.

Understanding of the characteristic features of science as a form of human knowledge and enquiry

Awareness of how science and technology shape our material, intellectual, and cultural environments,

Willingness to engage in science-related issues and with the ideas of science, as a reflective citizen.

The first point refers to the application of scientific knowledge and the process of scientific inquiry. The second point concerns with the nature of scientific knowledge, and the third point is close to STSE. The last point is about attitudes towards science and STSE awareness. Based on this definition, a framework for the assessment of scientific literacy has been worked out by PISA, in which students are assessed on three competencies: identifying scientific issues, explaining phenomena scientifically, and using scientific evidence.

Scientific literacy, as defined above, has many shared goals with STSE education, making STSE approach a potentially appropriate means for achieving the goal of scientific literacy. Indeed, STSE has been the slogan for achieving scientific literacy in some countries such as Canada in the past decades (Aikenhead 2000). As stated in the national framework of science curriculum in Canada, scientific skills, knowledge and attitudes are best acquired through “the study and analysis of the interrelationships among science, technology, society, and the environment”.