Rhetoric, good intentions, and enthusiasm aside, do students actually benefit from studying science through an STS approach? Science educators have claimed that there is insufficient research on STS instruction to answer the question with confidence (Cheek, 1992a; Eijkelhof and Lijnse, 1988; Rubba, 1987b; Finley, Lawrenz and Heller, 1992). This chapter comes to a different conclusion: Students can benefit from learning science through STS, and they benefit quite consistently.
Arguments in favor of STS education often assert lofty goals; for instance, to produce wise decision makers, an empowered citizenry, an enlightened democracy, a socially responsible corps of scientists and engineers, or an increased number of scientists and engineers (particularly women). These goals involve incredibly complex psychological and sociological interactions. Although such goals may inspire educators, their complexity defies evaluation. Lofty goals, therefore, make poor criteria for evaluating student outcomes of STS instruction.
More modest aims of STS education will better serve as criteria. Most STS science syllabi embrace four common aims (Aikenhead, 1986; Bybee, 1985b; Eijkelhof, 1990; Solomon, 1993): (1) to increase citizen's scientific literacy; (2) to generate student interest in science and technology; (3) to encourage interest in the interactions among science, technology and society; and (4) to help students become better at critical thinking, logical reasoning, creative problem solving, and especially decision making. (See section 1 and chapter 5 of this book for an
extensive description of STS aims.) Different educational groups around the world will operationalize these common aims differently (for example, Bybee, 1987; Chambers and Turnbull, 1989; Cheek, 1992c; Fensham, 1988; Waks, 1987b; Yager, 1992a).
The diversity of viewpoints on STS informs this chapter's review of research on student outcomes of STS science instruction. Different researchers will investigate different outcomes of STS instruction because of the researchers' different conceptions of STS (ranging, for example, from case studies in the history of science to political action on a local controversy). This chapter does not presuppose a single definition of STS for all to use. Instead, it accepts the diversity of views on STS that have guided research studies in science education. The chapter also examines an often-heard fear that STS science may not adequately prepare students for future science classes.
A two-part question, therefore, frames this research review: Do students actually benefit from, or are they harmed by, studying science through an STS approach?
The scope of my review is necessarily delimited. These delimitations are identified in the next section in a way that sheds light on the research review itself.
Science education research of the 1960s reached an unambiguous conclusion: the classroom teacher will influence student outcomes far more than specific curricula, textbooks, or teaching strategies (Welch, 1969). Thus, student outcomes from the same STS course can vary significantly from one teacher to another. Within any population of teachers there will be three groups: (1) those whose philosophy of science education is consistent with an STS approach, (2) those who are diametrically opposed to an STS approach, and (3) those in the middle who can move in either direction due to persuasion or by the requirement to use certain materials. All three groups will have their own influence on student outcomes. The research data presented in this chapter relates to the impact of STS science on students, and therefore must be carefully weighed in light of the teacher variable.
STS science instruction has relevance to a student's everyday world. Evaluators wanting to assess student learning are often dismayed by the fact that the STS content to be learned in school (formal education) can also be learned in the everyday world (informal instruction), notably from the mass media (Solomon, chapter 10; Lucas, chapter 11). The mass media is another "menacing" variable influencing student outcomes of some STS projects. Hence, if a student becomes more knowledgeable about STS content, was it due to good STS science teaching or to an out-of-school source? This problem is acknowledged, but a solution is illusive.
Another issue arises from an STS course's explicit connection to a student's everyday world. While such relevance usually enhances student motivation, and therefore achievement (Mesaros, 1988), relevant contexts may to some extent obfuscate the acquisition of science content and solving science problems (Solomon, 1987). Students tend to experience difficulty when mentally moving between the theoretical world of pure science concepts -- characterized by logical reasoning with evidence -- and their everyday world of commonsense concepts -- characterized by social interactions and consensus (Lijnse, 1990; Solomon, 1984). If STS science expects students to learn the science content in enough depth to use it in everyday situations (rather than to memorize it for the benefit of an examination), then STS science has taken on a much more rigorous task than traditional science has, as evidenced by the work reported by Harrie Eijkelhof in chapter 19. The central issue comparing STS and traditional science teaching, therefore, could be task difficulty, rather than STS content. The problem requires more research before valid conclusions can be reached.
STS instruction is comprised of both lesson content and teaching methods. Although content and methods are often interdependent, this chapter emphasizes the content aspect of STS instruction. Before embarking on this task, however, some succinct comments on the research on teaching methods are relevant.
Traditional science teaching methods tend to be characterized by convergent thinking and lecture-demonstrations. STS science instruction, on the other hand, demands a wider repertoire of teaching strategies such as divergent thinking, small group work, student-centered class discussion, problem-solving, simulations, decision making, controversies, debating, and using the media and other community resources (Aikenhead, 1988b; Solomon, 1989, 1993).
There is little research identifying the effects of these teaching strategies on STS instruction itself (Hofstein et al., 1988). Notable exceptions include the Discussion of Issues in School Science (DISS) project, a research program based on small-group work and applied specifically to STS science content (Solomon, 1988a). The DISS project documented students' capabilities at conducting effective small-group discussions on science-related social issues. (Its effect on student understanding of STS content is reviewed later in this chapter.) Byrne and Johnstone (1988) generalized the efficacy of small-group discussions. In an article entitled "How to Make Science Relevant," they concluded: "It is the achievement of interactivity, rather than the exact format, whether it be simulation, group discussion or role playing, which is central to attitude development" (p. 44). Attitude development is a key goal of STS instruction. Attitude was embodied in two of the four common aims of STS education stated at the outset of this chapter.
Interactive learning approaches are often identified as being essential to STS science instruction (Solomon, 1987, 1993). The research evidence suggests the following (Byrne and Johnstone, 1988):
1. In terms of learning science content, simulations and educational games can be just as effective as traditional methods. In terms of developing positive attitudes, simulations and games can be far more effective than traditional methods.
2. In terms of attitude development, the strategies of role playing, discussion and decision making can be highly effective.
3. "Group discussion can stimulate thought and interest and develop greater commitment on the part of the student." (p. 45)
4. In terms of promoting an understanding of the processes of science, an analysis and evaluation of historical case studies can be effective.
According to students engaged in simulations in the STS textbook Logical Reasoning in Science & Technology (described in chapter 20), the concrete connections between the academic science content and the student's everyday world made the academic science more interesting to learn for 80% of the students, compared with 8% who found simulations of little or no value.
What benefits accrue to students studying science through STS? The impact of STS instruction can be assessed by comparing its outcomes with the objectives of an STS project, or with the outcomes of traditional science instruction.
Based on a decade of research on National Science Foundation funded curriculum projects in the United States, Welch (1969) warned of the pitfalls of "horse race" evaluation studies (course X versus course Y). Such studies tend to follow experimental designs too simple to capture the complexity of classroom life and student outcomes. Nevertheless, consumers of research on STS tend to have a dichotomous view: status quo versus the new development. This chapter takes seriously the dichotomous view of those consumers.
Before comparing the success of STS and traditional science teaching, it is enlightening to remind ourselves how successful traditional science teaching is at accomplishing its primary objective: to produce knowledgeable human resources for the professions of science and engineering and for a democratic public working in an industrialized society (Majumdar et al., 1991). Deficiencies in the outcome of traditional science teaching have been the cornerstone of arguments supporting an STS approach. Section 1 of this book is replete with evidence and arguments; for instance, traditional science education has failed to produce an adequate and qualified cadre of scientists and engineers in the U.K. and U.S.A. (Bondi, 1985; Hurd, 1989). Traditional science education has succeeded at mystifying the general public by sustaining such myths as objectivity and certain truth (Aikenhead and Ryan, 1989; Bondi, 1985; Lederman, 1992; Millar and Wynne, 1988).
What is the impact of STS science instruction? The question is answered in three parts: (1) by examining the research into the attainment of STS objectives, (2) by examining the research into formative evaluation of STS projects, and (3) by examining some research into the current status of traditional science education related to STS.
Attaining STS Objectives
Table 5.1 in chapter 5 describes a variety of approaches to teaching science through STS. The following review is generally organized according to the categories in Table 5.1, beginning with an examination of the effects of "category 1" teaching, then moving to instances of higher category instruction, and ending with "other studies" -- those difficult to categorize according to Table 5.1.
Category 1 (Motivation by STS Context). No research has been conducted in STS classrooms where STS content is used for the sole purpose of motivating students to learn science content. In terms of learning STS content such as the nature of science and scientists, however, research from the 1960s indicates that such content is not generally learned by students when it is not evaluated by the teacher (Aikenhead, 1973; Hurd, 1971). Similarly in a category 1 STS class, little learning about STS content would be expected because that content is not evaluated. Motivation by STS content holds little promise for meeting STS objectives in science classrooms.
Category 2 (Casual Infusion of STS Content). Two studies into the effects of introducing STS vignettes (short anecdotes related to STS content along with periodic class discussions) into science classrooms showed no effect on students (Rubba, McGuyer and Wahlund, 1991). After six weeks, experimental and control students were similar in their (1) awareness of current STS issues, (2) perceived importance assigned to current STS issues, and (3) achievement on teacher designed tests on science content.
Category 3 (Purposeful Infusion of STS Content). Six History of Science Cases (Klopfer, 1966) were developed to teach a number of concepts dealing with social issues both external and internal to science (the nature of science, scientists, and the scientific enterprise). In an exemplar research study, two history of science case studies in each of biology, chemistry and physics were inserted into regular science classrooms, randomly chosen in the United States (Klopfer and Cooley, 1963). Each case study required two weeks of instruction time. Students were tested on the STS content as well as on the science content of the course. Four weeks of instruction, infused at different times during the school year, made a significant difference to students' attaining the modules' STS objectives. At the same time, the "experimental" STS group fared equally well on standard subject matter tests compared with the control group which made no gains on STS content.
History of science infusions into U.K. middle years classrooms showed similar results. Teachers chose between six and 13 units from Exploring the Nature of Science (Solomon, 1991) and used short activities (poster making, experiment, role playing, etc.) to encourage students to examine the text carefully (Solomon, Duveen, Scot and McCarth, 1992). Data from student interviews and questionnaires documented the conclusion:
[T]here is a significant move away from serendipitous empiricism and toward an appreciation of the interactive nature of experiment and theory. Experiments are seen to be designed for trying out explanations, and hence carry an expectation about what may happen. The theories the pupils hold are now less likely to be just facts, but like experiments, are related to explanation or prediction. (p. 418)
Moreover, preliminary evidence suggested that "studying the history of a change in theory may make the process of conceptual change a little easier" (p. 419).
Harvard's Project Physics course (Holton, Rutherford and Watson, 1970) was designed to systematically weave humanistic objectives into a traditional physics offering. Its major goal was to reverse the downward trend in physics enrolments in high schools (Welch, 1973). To accomplish this goal, humanistic aspects of physics (mostly social issues internal to the scientific community) were systematically infused into the course and were systematically assessed. Extensive, state-of-the-art, evaluation studies showed that Project Physics did reverse enrollment trends (Welch and Rothman, 1968) and did cause students to achieve a number of STS objectives not achieved by other physics curricula claiming similar objectives (Aikenhead, 1974). Achievement on standard physics tests did not suffer.
Thomas (1985) showed how grade 10 students developed the skill of structuring arguments on social issues related to science. By studying two STS modules infused into a regular science class, most students learned to find evidence, warrants, and rebuttals in arguments related to nuclear war and to global starvation. Critical thinking can be improved with STS materials that emphasize those skills.
A U.S. high school chemistry course was changed into an STS chemistry course by implementing a six-week instructional model that involved students in chemistry-related social issues (Pedersen, 1992). Students were required to define a social issue, research it, construct an arguable position, participate in a "public meeting," attempt to reach a consensus with the class, and finally, involve oneself in a course of action. The experimental (STS) students significantly out-performed the control students in three areas: attitudes toward science, anxiety toward science, and problem-solving perceptions. In a fourth area, chemistry achievement, there was no difference between the two groups.
In a different American study, grade 7 students participated in a four-week STS biology module that dealt with four aspects of STS instruction (Wiesenmayer and Rubba, 1990): the STS foundation level, the STS issue awareness level, the STS issues investigation level, and the STS action skills development level. Students who studied the module made significant gains in achievement on STS content compared with students who did not. The achievement was assessed with respect to: (1) knowledge about the interactions among science, technology and society, (2) awareness of STS issues, (3) knowledge and skills necessary to investigate STS issues, and (4) knowledge about citizenship actions.
Another technique that infuses STS content purposefully into a science course is the use of video "news clips" to initiate student-centered small-group discussions throughout a science course (Solomon, 1993). Students participating in the DISS (Discussion of Issues in School Science) project demonstrated the skills needed to engage in meaningful discussions without the help of an adult. As a result of those discussions, students became more cognizant of their civic responsibility to be more self-reliant in making up their own minds on an issue, rather than relying on an expert. Similar results, established through a decade of research in the U.S., show that students' social responsibility is fostered by STS courses that (1) involve students in investigating STS issues, and (2) attempt to resolve those issues (Ramsay, 1993; Rubba, 1987a).
In summary, purposeful infusion of STS content can make a difference to attaining STS objectives without jeopardizing student achievement in traditional science content. On the other hand, students who follow a traditional syllabus show no advantage in science content achievement and make negligible gains on STS content achievement.
Category 4 (Singular Discipline Through STS Content). STS materials classified as category 4 or above depart from the structure and the focus of traditional science courses. These STS materials usually raise questions in teachers' minds about what is worth teaching in the name of science (Roberts, 1988). Science teachers, individually or by committee, are the ones who normally decide what materials to use in their classroom. These decisions are seldom based on the results of research with students. This situation does not encourage STS developers to evaluate their materials in terms of the impact materials have on students.
All too often the responsibility for assessing the impact of the STS materials resides in the hands of one person or a small team of educators. Understandably, their priority is the quality and acceptance of the materials. These developers channel all their energy into product quality and the politics of implementing non-traditional materials. Thus, little attention is normally given to research.
A notable exception is the PLON project (Eijkelhof and Kortland, 1988). Extensive research on the project's 40 modules included a systematic analysis of student's reception to those materials. In a later section of this chapter, more will be said about the PLON research that informed the revision process used to improve the modules (formative evaluation). In chapter 19, Eijkelhof describes a specific PLON study that demonstrates exemplary research methods and yields enlightening results. In terms of the present topic -- attaining STS objectives -- the following summary is offered. Similar to the results of Harvard's Project Physics, PLON students attained the STS objectives to a reasonable degree while showing no differences, compared with non-PLON students, on standard physics questions (Eijkelhof and Lijnse, 1988). One of PLON's objectives, to promote the use of physics knowledge in everyday situations, was partly accomplished. Traditional physics courses that include similar rhetoric in their objectives offer no empirical evidence to support their claim that their materials successfully promote the application of physics to everyday situations. One of the most significant outcomes of the PLON research program is its in-depth research on learning physics subject matter and on determining what subject matter should be taught from an STS point of view (Eijkelhof, 1990; Eijkelhof and Lijnse, 1988).
CEPUP (Chemical Education for Public Understanding Program, 1991) developed eight STS modules for students aged 11 to 15. As described by Herb Thier and Barbara Nagle in chapter 8, the modules highlight chemical concepts and processes associated with current societal issues such as toxic waste, risk analysis, groundwater, and determining threshold limits. CEPUP has undertaken several comprehensive research studies to assess its impact on students. CEPUP students made significant gains, compared with their non-CEPUP counterparts, in the following areas (Kelly, 1991): perceived empowerment in dealing with chemical pollution; favorable perceptions of the chemical industry and of the media; and understanding risk, the nature of science, the processes of science, and science concepts.
Categories 5 to 8 (Science Through STS Content etc.). Classroom materials classified in categories 5 to 8 tend to integrate various science disciplines. Although the issue of integration itself is not addressed in this chapter, one general statement can be made: Most researchers agree that students in integrated courses learn the traditional subject matter as well as students in discipline-centered courses, but that high school teachers are uncomfortable with integrated science (Chamberlain, 1985).
Given their cool reaction to integrated science, traditional science teachers are even more uncomfortable with the degree of STS content found in courses classified in categories 5 to 8. As a result, developers are usually preoccupied with the concerns of science teachers, which leaves little time for research with students. Some studies, however, have demonstrated that STS objectives can be achieved.
Zoller et al. (1990) looked at the impact of Science and Technology 11 (a category 6 course) on grade 11 students, with respect to five major objectives. The selection of these objectives for assessment was determined by the availability of pertinent and valid evaluation questions. The researchers used four questions from a pool of 114 STS items known as Views on Science-Technology-Society, VOSTS (Aikenhead, Ryan and Fleming, 1989; Aikenhead and Ryan, 1992), and conducted a matched-pair investigation of students who had studied the new STS course (ST11) and those who had not (non-ST11). Rather than treat a student's choice as correct or incorrect, Zoller et al. (1990) analyzed the students' response patterns. The researchers identified the ideas that students chose in response to a VOSTS item. For three of the four VOSTS items, the ST11 student responses were significantly closer to the course's objectives than were the non-ST11 responses. The Science and Technology 11 course made a significant difference. In a follow-up study, Zoller, Donn, Wild and Beckett (1991) corroborated these results, and more. By comparing students' views with their teachers' views, Zoller et al. (1991) concluded that the positive effects of the STS course were achieved through "education" rather than by "indoctrination."
It is interesting to see what happened with the fourth VOSTS item, the one that showed no difference between the ST11 and non-ST11 groups (Zoller et al., 1990). Students predominantly form their views on STS topics from their culture, particularly the mass media (Aikenhead, 1988a; Solomon, 1993). STS instruction would be expected to "correct" any naive or out-of-date ideas picked up by students from the mass media. However, if an objective of an STS course harbored the same misconception found in the media, then the instruction would not likely alter students' views on that topic. Such was the case with Science and Technology 11 and its definition of technology: the application of the concepts and principles of science. Contrary to this view, technology is not applied science (Collingridge, 1989; Fleming, 1989; Layton, chapter 4; Snow, 1987). If a simplification must be stated it should read, "Science is applied technology" (McGinn, 1991). The instances of technology-driven science far exceed the instances of science-driven technology (Ziman, 1984). Science and Technology 11 perpetuated an out-dated concept of technology, a concept embraced by the media and shared by the teachers of the course (Zoller et al., 1991). Therefore, the STS course did not influence students' misconceptions of technology.
Another full-year course, Science: A Way of Knowing (Aikenhead and Fleming, 1975), claimed to teach STS objectives. Research showed that a number of these objectives were attained (those that received explicit and repeated emphasis in the course); for example: "the distinction between science and technology, the relationships between the two, the importance of open communication to the advancement of science, the tentativeness of scientific knowledge, some human characteristics of scientists, and the role of science in helping to solve social problems" (Aikenhead, 1979b, p. 127). The effect of Science: A Way of Knowing on student achievement on traditional science content is discussed in a later section, "Fear Over Students Missing Essential Science Content."
STS and environmental education (EE) share common objectives. For instance, STS and EE "will empower [students] to use the values, habits, knowledge, and processes of both science and democracy to cope with both personal and societal decisions" (Ramsay, 1993, p. 243). In his review of U.S. research on EE, Ramsay (1993) amplified Kortland's (1992) findings when he concluded (1) little impact on students' social responsibility occurred as a result of STS instruction that used sterile simulations and emphasized science knowledge (for example, ChemCom, chapter 9), but (2) significant impact occurred when students investigated real STS issues and attempted to resolve them.
An intriguing result emerged during an evaluation of Salters' Science (UYSEG, 1991), a series of courses for 11- to 16-year-olds. Salters' Science puts great emphasis on learning science in everyday contexts. Although their modicum of STS content was not assessed per se, Ramsden (1992) found that students' interest and enthusiasm were significantly peaked by the courses. But she discovered that the more students enjoyed Salters' Science, the less they perceived it to be science.
The objective to improve the decision-making capability of students is often prominent for most STS instruction in categories 5 to 8. Decision making is a very complex process (Aikenhead, 1985a; Piel, 1993). The interplay between science content and decision making on a science-related social issue has been explored, but the results are conflicting (Fleming, 1986; Iozzi, 1979; Solomon, 1988b). Yet a recent in-depth analysis of small-group discussions over STS issues (part of the DISS project) revealed a subtle way in which students incorporate scientific content into their discussions (Solomon, 1993). Similar subtleties were observed by teachers who used student-centered discussion when teaching Logical Reasoning in Science & Technology (chapter 20). Promising new avenues of research into student decision making were recently explored by the Dutch Environmental Education project (Kortland, 1992). This work is reviewed below in the section "Formative Evaluation."
In summary, although more research is required to illuminate the impact of recently developed STS science courses classified in categories 5 to 8 of Table 5.1 (chapter 5), initial evidence encourages the view that many of the more modest STS content objectives can be
attained, including the improvement of students' orientation toward social responsibility.
Other Studies. Written responses to a British examination for an STS syllabus were analyzed by Solomon (1988a), who concluded that explicit instruction can make a difference, but that the STS content is rather difficult and challenging to students.
Interesting results are found in an extensive research program that dealt with the impact of STS instruction on students in grades 4 to 9 taught by teachers who participated in the Iowa Chautauqua project (Yager, Blunck, Binadja, McComas and Penick, 1988). Compared with the projects reviewed above, the STS instruction stemmed much more from a "grass roots" approach to developing STS instructional materials. (See Bill Williams, chapter 6, for more details about the grass-roots approach.) During four years of research, about 300 teachers participated in three-day workshops on STS. Each workshop emphasized that STS instruction is oriented toward local social issues. The participating teachers designed a one-month STS module on their own. Their own students and a control group of students were pre-tested and post-tested on a battery of instruments and evaluation techniques (Yager and McCormack, 1989). These teachers returned for a second workshop to share their results with peers. Some teachers became leaders in subsequent workshops. STS instruction was shown to have a significantly greater impact on students in the following ways:
1. Students become more capable at applying science concepts to new situations (Varrella, 1992).
2. "Students are better able to apply information, to relate information to other situations, to act independently, and to make decisions" (Yager, Blunck et al., 1988, p. 7).
3. Attitudes towards science classes, towards the perceived usefulness of those classes, and toward science careers, were much more positive (Banerjee and Yager, 1992).
4. Students displayed much higher frequencies of creativity (Penick, 1992).
5. Science process skills achievement was twice to three times better in STS classes (Binadja, 1992).
At the same time, the acquisition of traditional science content was the same or significantly better for STS students compared with the control group (Meyers, 1992). "STS efforts may be effective where traditional approaches fail because students start with their own problems, collect their own data, apply it to their problems, and make decisions regarding their action" (Binadja, 1992, pp. 99-100). In summary, STS instruction consistently appears to augment student achievement on STS content without interfering significantly with the acquisition of traditional science subject matter. This conclusion raises the question: How much time can be spent on STS content before making a difference to student achievement on traditional science content? The question is answered later in the section "Fear Over Students Missing Essential Science Content."
Formative Evaluation to STS
The research reviewed above was designed predominantly to inform decision makers and science educators about the effects of STS science instruction (summative evaluation). Another function of research is to inform the developers of classroom materials on how to modify those materials in order to better achieve the developers' objectives (formative evaluation). Formative evaluation provides systematic feedback to the designers and writers of STS materials. The formative studies reviewed here demonstrate the impact that STS instruction can have on students.
One finds very few formative evaluation studies published in the literature because information on obsolete modules is of little interest to other educators, or because few STS projects have the resources to collect evidence on student outcomes. Too often developers rely simply on teacher reaction to what went smoothly and what caused problems in the pilot classrooms. Three projects, however, PLON, Environmental Education, and NYSTEP, have published formative evaluation data.
The PLON and Environmental Education projects are exemplars for all STS educators. They demonstrate how modifications can be made to materials by systematically collecting feedback from students and acting on that feedback. For example, early versions of PLON materials tended to be too ambitious and too general in focus and these versions were completely rewritten (Eijkelhof and Lijnse, 1988). Some of the details on the PLON formative evaluation are presented by Harrie Eijkelhof in chapter 19.
The Environmental Education projects' formative evaluation collected data on students' ability to engage in decision making (Kortland, 1992). Three criteria were used to assess student achievement: range of alternatives, depth of argumentation, and weighting of arguments. Evidence clearly showed a significant improvement in the range of alternatives that students would generate, but no change was observed with respect to the depth and weighting criteria. Kortland also discovered a gulf between students' positive attitudes toward a decision reached and their behavioral intention to carry it out. The Dutch project represents a rare foray into assessing the STS goal of decision making.
A set of 12 STS modules produced for middle-level science courses by the New York Science Technology and Society Project (NYSTEP) deals with science-related social issues such as waste management, epidemics, global warming, and communication. Formative evaluation data collected during field trials showed that students' awareness of societal problems increases and that the modules made an impact on the communities in which they are implemented (Cheek, 1992b).
A different approach to formative evaluation is illustrated in chapter 20. During the development of a textbook for a grade-10 STS course, Logical Reasoning in Science & Technology, LoRST (Aikenhead, 1991a, b), I became a participant observer in pilot classrooms, teaching the first version myself and then sitting in three classrooms watching untrained teachers teach a revised version. I revised the material again in a way suggested by students themselves, I added material that students asked questions about, and I reacted to problems that naturally arose in the classroom. Thus, the learning objectives of LoRST would likely be achieved to some noticeable degree as evidenced by the modifications to the textbook, modifications based on student achievement itself.
In summary, although the results of formative evaluation inform the revision of student materials or an accompanying teacher guide, the documentation of these results, while seldom reported, suggests that the objectives of STS materials can be attained to varying degrees. These results add weight to the findings of summative evaluation studies reported above.
Current Status Reports
STS science educators are interested in students' preconceptions related to STS content. These results serve as base-line data against which results of STS instruction can be compared when assessing education achievement. A survey of student familiarity with STS content has been used to inform policy statements about science education achievement (Bybee, Harms, Ward and Yager, 1980; Hueftle, Rakow and Welch, 1983). Current status studies also yield data on the effectiveness of traditional science instruction at conveying accurate STS content. Research data can pinpoint "remedial" content needed in STS materials. Examples are summarized here.
Canadian students' reasoned beliefs were documented on a wide range of STS topics using the STS assessment instrument Views on Science-Technology-Society, VOSTS (Aikenhead, Ryan and Fleming, 1989; Aikenhead, Ryan and Désautels, 1989; Ryan and Aikenhead, 1992). Results from these 17-year-olds indicated that: (1) views on the nature of science tend to be naive, (2) views on technology reflect the gadget orientation found in Solomon's results (1988a) in the U.K., and also reflect the out-dated notion prevalent in North America that technology is simply applied science, (3) the internal social aspects of science make intuitive sense to 17-year-olds, (4) the external social aspects of science are seen to be shaped to some extent by culture and the mass media, and (5) students only moderately associated social issues with science and technology. Results from VOSTS are currently being used by science educators as base-line date for their own research and teaching (for example, Visavateeranon and Finley, 1993).
Research data can suggest remedial content needed in STS materials. The VOSTS research in Canada revealed that half of the sample of grade 12 Saskatchewan students did not understand the meaning of "objective," as in "scientists are objective in their work" (Aikenhead, 1988a). As a consequence of this research, a section "Subjective versus Objective" was written into an STS textbook being developed at that time, Logical Reasoning in Science & Technology (chapter 20).
Millar & Wynne (1988) monitored public views about science, views so native or erroneous that they would be detrimental to interpreting or coping with STS issues. Similar negative effects on decision making have also been described by Aikenhead (1985a, b), Layton (1986), and Layton et al. (1986), who discovered that the knowledge most useful to adults making decisions is the knowledge of the nature of science and how scientists work, rather than a compilation of scientific facts and concepts (traditional science content).
STS instruction can make an appreciable difference to a student's understanding of STS content (STS interactions, the nature of science and technology, and the social issues within and outside the scientific enterprise), to a student's thinking skills, and to a student's attitude toward science. Although student understandings and attitudes can be resistent to change, the high degree of interest and enthusiasm that students express for STS instruction indicates that future developments toward STS instruction will receive encouragingly positive reaction from most students.
A favorable student response to STS instruction is one thing, the reaction of traditional science teachers is quite another issue. This chapter ends by addressing traditional teachers' fears that STS science will be detrimental to their students' future study of science.
High school teachers who defend traditional science instruction warn that time spent on STS content diminishes preparation for university science courses. Fewer science concepts will be learned and general achievement will suffer. Is there any validity to these claims? The answer is a qualified "no."
The studies reviewed above in this chapter have shown that standardized measures of achievement on science content are virtually unaffected by infusing STS content into science courses, or by reorganizing the science content in ways defined by an STS issue.
Further studies have been undertaken in the U.S.A. to determine if high school science courses make any difference at all to students' achievement at university. In other words, what happens to students, enrolled in a university science class, who neglected to take the prerequisite science course at high school? Although this extreme case of ignoring a prerequisite is certainly not desirable, the situation does shed light on the issue of possible harm of studying science through an STS approach.
Science teachers are understandably concerned about their academically talented students' achieving successful careers in science and technology. (The "less talented" students normally do not take career-oriented university science courses.) What does a high school chemistry or physics course contribute to students' achievement in first-year university science? The research evidence is clear. The courses contribute essentially nothing.
Whether or not students study chemistry or physics in high school has no correlation with their science achievement in first-year university or college (Champagne and Klopfer, 1982; McCammon, Golden and Wuensch, 1988; Tanaka and Taigen, 1986). On the other hand, students' ability in algebra and critical thinking, and their school ranking, does have a weak correlation with university science achievement. Success in university science courses relies much more on personal attributes such as study habits, curiosity, motivation, creativity, and intellectual brightness (Razali, 1986; Stuart, 1977; Susilo, 1976; Thomson, 1975). While this result is often acknowledged by university science professors, it would seem to be a well kept secret from high school science teachers. Most traditional science teachers will tell you that the skills and knowledge measured by biology, chemistry and physics achievement tests are essential for success in university science courses (Ogden, 1975). They are wrong (Razali, 1986; Stuart, 1977; Susilo, 1976; Thomson, 1975).
Two experiments were undertaken in which first-year university physics and chemistry courses were taught to the more academically talented students, of whom half had not taken the prerequisite in high school (Yager and Krajcik, 1989; and Yager, Snider and Krajcik, 1988). In both experiments, students who had not taken the prerequisite course performed as well as those who had, based on their final examination mark, their course grade, and their attitude toward the subject. The only difference was the amount of tutorial time sought out by students. Those who had not taken the high school prerequisite asked for more help. In a related study, Stanley and Stanley (1986) were able to condense the United States' full year, high school biology, chemistry and physics courses into three-week summer school offerings for academically bright students.
During the field trial of Science: A Way of Knowing (Aikenhead and Fleming, 1975; a category 7 STS course, Table 5.1 in chapter 5), achievement comparisons were made between students who had studied the STS course in grade 10, and those who had taken the regular grade 10 offering (a traditional content prerequisite to 11th grade biology, chemistry and physics at that school). Comparisons were made the year following. By November of their 11th grade science course (biology, chemistry and/or physics), the achievement difference between students who had studied the STS course and those who had not was indistinguishable (Aikenhead, 1982). These results were particularly threatening to the traditional science teachers at that school. They successfully lobbied to have the STS course discontinued in their school.
The traditional high school science courses in North America do not stand up to scrutiny as well as one might expect. The research findings reviewed here raise a number of questions about high school science teaching, about standard measures of achievement, about first-year university science courses, and about science teachers' perceived mission in science education. The research does indicate that high school science prerequisites to university science courses in North America are not as sacred as science teachers hold them to be. Therefore, the fear that STS content will significantly diminish the amount of science content acquired by students, and thus compromise their achievement at university, seems to be unwarranted.
Obviously the issue of achievement in science is much more complex than portrayed by the succinct review here. Other factors, such as specialization over a number of years, seem to affect student achievement, as the IEA's Second International Science Study shows (Keeves, 1990).
The conclusion to be drawn here is not that high school science is irrelevant to university achievement. But rather, high school science, as narrowly defined by teachers representing a traditional perspective, is irrelevant to the objectives espoused by its defenders. The fear over students missing essential science content may be a manifestation of a fear of losing control over the science curriculum, over students, or more personally, it may be a fear of losing one's vision of oneself as a science teacher whose mission is to socialize high school students into a scientific discipline. Such a mission offers a seductive raison d'etre for maintaining the status quo in science education (Mitschke, 1993).
Only a small proportion of STS science projects have systematically investigated the attainment of objectives related to traditional and STS content. Over the years, however, numerous studies have been published. The accumulated body of research allows one to interpolate, extrapolate, and synthesize the following conclusions:
1. Students in STS classes (compared with traditional science classes) can significantly improve their understanding of (a) the social issues both external and internal to science, and (b) the interactions among science, technology and society; depending on what content is emphasized and evaluated by the teacher.
2. Students in STS classes (compared with traditional science classes) can significantly improve their attitudes toward science, toward science classes, and toward learning, as a result of STS content and as a result of STS teaching methods that incorporate student interactivity.
3. Students in STS classes (compared with traditional science classes) can make modest but significant gains in thinking skills such as applying science content to everyday situations, critical and creative thinking, and decision making, as long as these skills are explicitly practised and evaluated.
4. Student achievement on traditional subject matter at the next level of science education (at a higher grade level or at university) will not be significantly compromised by teaching science through STS. This result is particularly true for academically more talented students.
5. Students can benefit from studying science through an STS approach, provided: (a) the instruction is at least a category 3 type or higher (Table 5.1 in chapter 5); (b) appropriate classroom materials are available; and (c) a teacher's orientation toward science instruction is in reasonable synchrony with the STS approach expected to be used, as detailed by Peter Fensham and Deborah Corrigan in chapter 18.
Yes, students can benefit from learning science through STS, and they benefit quite consistently over their counterparts in traditional science classes. STS science education, therefore, provides a demonstrative advantage to students wishing to improve their scientific literacy.
In terms of improving STS education, the potency of research and development projects was evident in the literature. Such projects hold promise for educators who wish to improve or establish STS programs.