Campbell J. McRobbie and Gregory P. Thomas

The use of microcomputers in science laboratory activities is one promising application of computers as learning and teaching tools. Such an application is congruent with the broad goals of science education in that it seeks to provide opportunities for students and teachers to explore and understand workplace applications of science, to develop of skills of investigation, reflection and analysis, to generate or refine knowledge, to find solutions and to pose problems. Increasing the understanding of science studied and the development of higher level reasoning skills such as these are central to reform directions in science education (Bybee & DeBoer, 1994).

Microcomputer-based learning (MBL), or computerized data logging as it is often referred to, involves linking one or more sensors or probes to a computer so that the sensor's relayed signal can be viewed on the computer's screen as calibrated data either in tabular or graphical form. The data are usually available in real time, as investigations proceed. Increasingly sophisticated MBL systems are being devised and purchased and used by schools in their science laboratories for data logging, analysis of data, interaction with the student in the analysis of that data and the development of understanding of phenomena. The literature related to possible applications of MBL technology continues to increase with recent suggestions for their use (Soares & Creevy, 1995; Halford & Hoggins, 1995; Wild & Bateman,1995; Adamson, Zimmerman, & Nakhleh, 1997; Barton & Rogers, 1994) being illustrative of applications across physics, chemistry and biology education.

The potential of such technology to enhance learning lies in its ability to overcome barriers to learning including delays in processing results, observation of phenomena in multiple representations, and the capability of simultaneous multiple measurements (Nachmias, 1989, cited in Lazarowitz & Tamir, 1994). As most of the technical work is done by the computer it is proposed that the student is more able to think, solve problems, employ higher order thinking skills, and that continuous interaction with the experimental data should aid in the identification of alternate conceptions and conceptual change.

Rogers and Wild (1996) assert that it is "easier to describe data-logging activities than to define their benefits to pupils' learning and understanding of science" (p. 131) and that many reports refer predominantly to the technical aspects of the MBL use rather than measured learning gains. Some studies, however, have investigated students' learning outcomes. For example, Nakhleh and Krajcik (1994) found that students using MBL achieved larger positive gains in differentiation and integration of their knowledge of acids and bases compared to non-MBL users while Stein, Nachmias and Friedler (1990) found that MBL and non-MBL users both drew equally valid conclusions from data drawn from experiments investigating heat and temperature. Additionally, Friedler, Nachmias, & Songer (1989) and Friedler, Nachmias, and Linn (1990) reported a positive effect on the development of scientific enquiry skills for students using MBL technology. While such reports reflect the general promise of the use of MBL technology they fail to provide compelling evidence to support the implementation of MBL into school laboratories and curricula as a means of improving learning outcomes. The inconclusive nature of the effect of MBL on learning outcomes is summarised by Lazarowitz and Tamir (1994) who concluded that research is ambivalent as to whether the application of such technology does enhance learning.

Few studies have investigated what students and teachers actually do and why they do so as they use and interact with MBL technology, how it influences teaching and learning, and the significance of teacher and student variables such as beliefs about teaching and learning on its use. Hodson (1992) argues that until detailed studies are undertaken into what students actually do in laboratories we are unlikely to understand the pedagogic value of laboratories in learning. Accordingly, understanding why teachers teach and students learn as they do in current classroom learning and teaching environments is a sound base for developing an understanding of the pedagogical value of laboratory activities using MBL technology, and also for informing professional development and bringing about the change required for effective use of that resource (McRobbie & Tobin, 1995). Accordingly the purposes of this research were to (a) investigate how the beliefs of a teacher and students influenced the implementation and use of MBL technology in the chemistry classroom, (b) to investigate the student learning and thinking occurring using the MBL technology, and how that learning is utilized in the classroom by the students and teacher, and (c) to draw implications for effective application of MBL technology in the classroom.

An interpretive methodology concerned with "the immediate and local meanings of actions, as defined from the actors point of view" (Erickson 1986, p. 119) was adopted. The beliefs, experiences and actions of the teacher and students were interpreted through the lens of social constructivism. The benefits of the hermeneutic process, authenticity and trustworthiness (Guba & Lincoln 1989), were important considerations in the study and the analysis of the data. A single researcher visited the classroom each day for five weeks to observe a unit that explored gases and the gas laws. This prolonged engagement in the research setting also increased the authenticity and credibility of the data. The class consisted of 12 males and 9 females (15 - 16 years old) located in a metropolitan independent school in Brisbane, Australia. The students had previously studied chemistry as part of a general science course in years 8, 9 and 10.

Anne was interviewed on four occasions, twice before and twice after the MBL experiments, for a total of about four fours. During these interviews Anne was encouraged to respond to emerging assertions. This member checking enabled her to suggest changes to improve the authenticity of the data and the credibility of subsequent assertions. Prior to the MBL experiments all students were interviewed regarding (a) their responses on the pretest, (b) their responses on learning environment surveys, (c) their beliefs about the nature of practical work, teaching and learning, and (d) the use of the computers in the chemistry laboratory. Following the completion of the pre-MBL interviews, eight students spanning the range of responses for (a) to (d) above were selected for intensive study. Following the MBL experiments these eight students were interviewed regarding their responses on the post-test. Stimulated recall interviews with these eight students investigated their use of the MBL during two experiments which, respectively, investigated pressure-temperature and pressure-volume relationships in gases.

The data were interpreted by generating tentative assertions and questions regarding the teacher's and students' actions, and the reasons for their actions, from field notes, videotapes and daily reading of interview transcripts. We referred to the literature and what we already knew from previous studies in forming these tentative assertions and questions. Each assertion and question was explored in subsequent interviews with the participants, and new assertions arose in response to this process.

To present evidence that acknowledges the complexity of the life-worlds of both the teacher and students (Roth & McRobbie, in press) and is congruent with the our answers to the research questions in the discussion we present the results for the teacher and the students separately. For Anne, we use an interpretative account supported by evidence obtained through the use of various research methods which is typical of research into the use of MBL technology in science classrooms. Her story is in two parts; an initial investigation of her beliefs and her teaching using the MBL, and her response to the assertions raised with her by the researchers. We then present our account of students' use of the MBL technology using both (a) an interpretative account that seeks to provide a composite picture of students' use of the MBL and (b) an experimental map (Gooding, 1992) that seeks to represent the use of the MBL by a group whose actions and thinking were typical of the class during the experiments. These means of presenting students' actions are complementary and provide alternative windows for understanding their use of the MBL.

The experimental maps use a notation derived from Gooding (1992) and adapted by Roth, McRobbie, Lucas and Boutonne (1997) which, together with a brief explanation, is described in Appendix A. Sequences of actions are represented by line segments with horizontal line segments representing new learning and vertical lines representing actions that lead to no new learning. Triangles represent goals and decisions. The outcome of manipulations on the material world (seeing, recording) are shown as squares. Mental operations, for example imagining, describing, and comparing are denoted by circles.

For two years Anne had collaborated with the head of the school's science faculty to introduce computers into the school's chemistry laboratories for use in practical work. "We were asked to think about what we could do for teacher appraisal...one of the things that was lacking in our labs was a computer which was linked up to experiments." Anne's expectations regarding the benefits of the implementation were congruent with the promise for the use of such technology previously outlined and expressed in the literature.

Despite her enthusiasm for the innovation Anne was increasingly aware that students did not utilize or understand the use of the MBL technology to the extent that she had initially expected. "We're still finding out things that aren't so flash because we're still in the early stages of using it. The kids aren't always totally aware of what they're measuring unless you really get them to say, 'What is it that we're measuring?' It's not that obvious to them." Generally, however, Anne was pleased with the students' performance in the laboratory, concluding, "I'm happy with how they do their practical work. They organize themselves reasonably well and they usually do the task. If I could change anything, I'd like to see them do more work outside [the classroom]."

Anne's teaching, by her own admission, was primarily didactic, based on objectivist semantics, and focussed on the transmission of knowledge rather than on providing a learning environment in which students socially constructed meaning.

Anne spent most of class time adopting a quantitative, rule based, algorithmic and mathematical approach to teaching about gases claiming, "This unit of work is very mathematical." Her belief in the mathematical nature of the gases topic led her to invoke the MBL technology as an important means of collecting data so that students could be convinced regarding the credibility of the mathematical relationships related to gases. "Sometimes kids are very hard to convince but if they have the evidence in front of them, they have to be convinced, even if it wasn't what they expected." It was the sole function of the MBL to supply data as the evidence for verifying gas laws.

Anne used a very structured format when introducing the two practical activities examined in this study. She outlined the aim of the experiment; introduced the apparatus specific to the experiment and briefly explained its operation; specified, and briefly discussed at a macroscopic relational level, the variables being examined; and related procedures specific to the experiment, for example, ensuring that the volume of gas in the tube attaching the syringe to the relay box was incorporated in the total volume of the gas. Students were given a very simple type-written procedure to follow. Anne justified this level of direction stating, "...basically kids need a very brief procedure so that they don't have to do much of the delicate work. If you have nice simple instructions, one, two, three etc., they're much more likely to read it and follow it through." She made no reference to how and why students' manipulation of the gas's conditions of containment affected the gas particles at a molecular level. Nor were students asked to relate changes in the macroscopic variables, measured using the computer, to simultaneous changes occurring at the molecular level as they altered either the temperature or volume of the gas.

During the practicals Anne was predominantly concerned with the logistics of the activities. Her primary concerns centred around ensuring that, (a) students were organized within their groups, "I've done the first part for you and you're up to number 2. You need someone to do this, someone to handle the syringe and the other person to make sure you're doing all the right things," (b) students completed the practical as quickly as possible, (c) students began answering the questions on the experiment's instruction sheets following their use of the computers, and (d) any difficulties associated with using the equipment were quickly rectified. During the Boyle's Law experiment Anne also spent considerable time collecting, and talking to students about, assignments and other chemistry work.

As students used the MBL technology she displayed little or no interest in either their use of the computers, apart from ensuring that it was being used as per her directions, or the data students obtained from it and the ramifications of that data. Anne expected that, as the students did the experiments, they would be thinking, "Firstly, are they connecting it up properly; secondly, what are the results coming out and are they what you expected." She expected a temporal demarcation between the observations that students made during the practicals and their interpretation of those observations.

While clearly acknowledging the potential of the MBL she was "...quite accepting of the fact" that students would not be thinking critically regarding data as it emerged on the computer screen claiming,

Discussion regarding data anomalies for both experiments was restricted to four short exchanges between Anne and individual students from three of the seven groups following their completion of the experiments. In these exchanges Anne expressed dismay at the data that had been obtained. For example, in the experiment investigating the relationship between the pressure of a gas a its temperature, it did not match her expectations because, in most cases, a straight line through absolute zero did not result from plotting pressure against temperature.

Only in one of the exchanges, with Sue, did Anne seek to thoroughly explore the data anomalies from one of the experiments, that which investigated Boyle's Law. She discussed with Sue possible reasons to explain why the data was "so far out"; "it is possible that someone changed one of the pieces of tubing affecting the volume"; "there could be a hole or a leak in there making the readings at high pressure least reliable"; and "it is possible that the gas inside the syringe was getting a bit hotter." She concluded the discussion by suggesting "...what we need to be able to do is to be able to explain why...so when you're answering the questions you can put that into your explanation." A review of Sue's prac report, which achieved the grade of A-, shows no reference to these data anomalies. This further supports the claim that exploration of such anomalies was not consistent with Anne's teaching priorities and that verifying the gas laws was the prime objective of the experiments involving the MBL.

Following the collection of data, the students were instructed to answer questions related to the practicals which were predominantly of the type, "Express in words the relationship between gas pressure and temperature" and "Write the mathematical equation for the line." Only one question related to the experiment which investigated the relationship between the pressure of the gas and its temperature, "Explain this relationship in terms of molecular velocity and collisions of particles," asked students to think beyond the relational level and explain their data with reference to kinetic molecular theory.

For both practicals Anne demonstrated to the whole class how to derive the laws from their data. As in the pre-experimental discussion, little in the way of cognitive scaffolding or modeling higher-level cognitive processes was provided for the students. Despite the extent of the unexpected data anomalies such anomalies were given little other than token attention to individuals and the class as a whole. Anne's review to the class following the temperature-pressure experiment confirmed her focus on the mathematical aspects of the chemistry, her superficial exploration of reasons for the unexpected data, and her lack of attention to ensuring that students used data gained from the experiments to understand the nature of the gas at the molecular level. While she communicated her impression that some students had sought to explain their results in terms of kinetic molecular theory during discussions with her, a thorough analysis of transcripts of her dialogue with students during and following the experiments failed to unearth evidence to support such a claim. Nevertheless, the reference to the effect of temperature on gas pressure in the following quote is her sole reference to the molecular nature of gas behaviour from her communication to the class regarding either experiment.

Students' views regarding the purpose and value of experimental work did not reflect the commonly accepted goals of experimental work in constructivist science classrooms. Ruth, like other students, stated "I like how we're being taught." Her views on the purpose and value of experimental work were also typical of class members.

Sue also communicated commonly held beliefs regarding the role of experimental work in the chemistry classroom.

During stimulated recall interviews students reported interpreting Anne's introductions as focussing on logistical and manipulative factors involved in the experiment. Lisa, a high achieving student whose views were typical of those interviewed, recalled "She was talking about how the machines worked and stuff, and how we'd be working in groups on the computers, and how that should only take a certain amount of time. She's telling you what to do." Jon, a pass grade student from another group, suggested that following the introduction his focus was going to be to, "Just operate the computer programme. Just press the buttons."

Analysis of data from the three focus groups suggests that the students were almost exclusively concerned with and focussed on, as they agreed in interviews, "...following the recipe" of the practical as directed by the teacher and obtaining the data. Within each group, the students allocated procedural tasks to each other and then rigidly adhered to those tasks. In one group, where the division of labour was typical of all groups, as Jason read the instructions Neil manipulated the syringe while Jon operated the computer. Jason commented on the extent to which task allocation affected his behaviour and thinking claiming that in the Boyle's Law experiment his responsibility was on ensuring that instructions were followed properly, "If everything didn't run smoothly I knew that everyone would be blaming me because I'm the one with the instructions."

The single-mindedness with which students sought to obtain their data resulted in several consequences. In some cases, thoughtful and reasonable questions of a group member were ignored to ensure that the collection of data continued uninterrupted. Jason confirmed and exemplified this obsession for data collecting stating, "The emphasis was more on getting it done and then thinking about it later." Students' interaction with the data as it appeared occurred at only a superficial level. Cleo, working in a third group separate from those of Jason's and Lisa's, asserted that she did not think about what the figures actually meant because she was "...concentrating on the experiment, what to do." In addition, students did not systematically or purposefully examine the multiple representations of data that were available on the screen in the form of tables and graphs. In stimulated recall interviews students unanimously reported not noticing coloured dots, representing the pressure of the gas at certain temperatures, as they appeared in a graph on the screen. These dots often became highly visible lines as the temperature of the gas came to the temperature of its water bath and the pressure of the gas altered accordingly. As the experiments proceeded no discussion regarding events occurring in relation to the gas at the molecular level, or about results in general, took place.

Students differed with respect to the quality of the learning they believed resulted from their use of the MBL technology. Some students, for example Lisa and Jason, suggested that the practical added little to their understanding of gas behaviour. Lisa commented, "In the computer pracs I knew what to expect because we'd already done it in class. They're just backing up what you've already learned in the textbook. I would have still had the same understanding after a certain time from something else." Ruth, Lisa's partner and the top achieving student in the class, further confirmed this. When asked if using the computer had made any difference to her learning she replied, "No. I don't think so. I don't think they're as hands-on as we usually do. You're just clicking buttons rather than actually doing it." Sue, a member of Cleo's group, and Jon suggested they could have learned the principles without the computer pracs but that, as they both stated "...it wouldn't have been as clear." Significantly, some students' alternate conceptions, identified on a pre-test, remained unchallenged as a result of the use of the MBL technology. These conceptions included the belief that gas particles clump together in the centre of their container or fall to the bottom of the container as the temperature is decreased, and that the volume of air in a syringe is not altered as the plunger is moved in and out.

The experimental map (Figure 1) shows the actions of one group of students during the experiment to 'discover' the relationship between the pressure of a gas ands its volume. The three students set up the computer and apparatus as per instructions. There are no horizontal lines indicating learning. The students were engaged in looking rather than observing. This experimental map is representative of the maps which could be drawn for the other groups that were observed.

1. Read instructions
2. Adjust volume

O'_{2,a,b,c,d,e,f,g,h,i,j}

Figure 1. Map representing Jason, Jon and Neil's investigation of the relationship between the pressure of a constant amount of gas and its volume. O'_{2,a,b,c,d,e,f,g,h,i,j} are possible observations that the students might have made but gave no indication of doing so during the experiment, discussions or interviews.

The students' use of the MBL technology and their related cognition were determined by the classroom context which was greatly influenced by, and strongly reflected, the teacher's beliefs. In Anne's class, there was little impetus for students to use the technology in the promising manner identified in the literature. A recent Australian study (Tinkler, Lepani, & Mitchell, 1996, p. 56) suggested that frequently too little is expected of students (often with tasks placed in a context that fails to motivate them)." Other studies (McRobbie & Tobin, 1995, 1997; Hand, Treagust, & Vance, 1997) have also found that there is little impetus for students to change and that their beliefs about teaching and learning are often congruent with those of their teachers, past and present. While some students claimed that the use of the MBL did little to enhance their learning, they were very accepting of such an outcome. Our immersion in the classroom for over 5 weeks leads us to suggest that the students had limited alternative experiences, in this or any of their past or present science classes, to base alternative expectations upon. For students to learn better in Anne's class, activities are required which better utilize the capabilities of MBL. Newton (1998) notes that persuasion may be needed to get students to explore data but that this "can be achieved if science questions are posed and pupil's activity set in a climate of inquiry" (p. 20). He adds that "pupils' preparatory and follow-up activity should be a more prominent feature of their experience" (p. 21). This climate of inquiry was absent in Anne's class, and she was aware of this. Her recourse to ascribing students' grades to their lack of effort is her interpretation of events and reflects her view of science education.

We do not propose that the potential of the use of MBL is unwarranted. Rather we propose that for such potential to be realised beyond its own publicity and rhetoric, teachers' and students' epistemologies and beliefs regarding teaching and learning must be taken account of as these are factors that strongly influence the implementation of this technology in the classroom. Rather than pretend that the implementation of such technology into science classrooms will have the desired effect irrespective of teachers' and students' beliefs we should be aware, as shown in this paper, that such factors are major obstacles to such implementation. Such a finding is not, of course, new. However, given the push to invest significant monies for the provision of such technology, it seems warranted that future research should further investigate the learning that results from the use of such technology and the factors affecting such learning.