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TEACHING WITH TECHNOLOGY
1 Biology Department, Salem State College, Salem, Massachusetts
2 Department of Biological Science, California State University, Fullerton, California
Address for reprint requests and other correspondence: M. A. Hoover, Biology Dept., Salem State College, 352 Lafayette St., Salem, MA 01970 (e-mail: mhoover{at}salemstate.edu)
Abstract
Live organisms versus digital video of the organisms were used to challenge students' naive ideas and misconceptions about blood, the heart, and circulatory patterns. Three faculty members taught 259 grade 10 biology students in a California high school with students from diverse ethnolinguistic groups who were divided into 5 classes using microscopes (128 students) and 5 classes using digital video (131 students) to compare blood transport among invertebrates, fish, and humans. The "What Is Happening in this Class?" (WIHIC) questionnaire was used for assessment of microscope and video groups to detect students' perception of their learning environment following these teaching interventions. The use of microscopes had a clear effect on the perception of the investigative aspects of the learning environment that was not detected with the video treatment. Findings suggest that video should not replace investigations with live organisms.
Key words: laboratory instruction; physiology education; science education; learning environment; cardiovascular
THE DISCIPLINE OF BIOLOGY is undergoing a revolution. Its major focus–understanding life–remains unchanged. However, the breakthrough discoveries of the second half of the 20th century, combined with new and emerging technologies and techniques, are transforming the kinds of questions that biologists ask and the ways investigations take place at the frontiers of the life sciences.
Approaches to biology education have also changed. In the 19th century, most biological discoveries emerged from an inductive process that started with gathering of facts, and yet the inductive method was not taught until quite recently. Laboratory instruction was not the norm until the 20th century. A report (8) about a Brown University zoology laboratory with dissection of cats and other animals in 1895 is among the first indications of laboratories as a component of biology instruction. Instead of teaching research methods, biology was taught in the 1800s through lectures with an emphasis on the knowledge of facts (8). As early as 1890, the New York State Regents exam for high school students required students to "design experiments," and so the backlash against "dry bones" procedures of laboratories started soon after laboratory instruction became the norm (8). In 1910, the American philosopher and educator John Dewey offered his criticism with the comment that "a student may acquire lab methods ... as he may so acquire material from a textbook ... without it ever occurring that they have anything to do with constructing beliefs that alone are worthy of the title of knowledge" (8). Dewey then described "a complete act of thought" that involved suggesting possible solutions and reasoning about ideas that could be tested with further observation or experimentation leading to acceptance or rejection. The steps of Dewey's approach were published in 1918 by William Kilpatrick of Teachers College as the "project method" (8).
In the last quarter of the 20th century, laboratory instruction became increasingly associated with an intellectual process, with new approaches to teaching based on emerging theories of learning, the empowering nature of new technologies, increasing emphasis on research experiences, and changes in the manner in which people work together to investigate. Principles of learning from cognitive research suggest the importance of designing instructional units that integrate laboratories with lecture and discussion (8). This suggestion was supported with the finding that undergraduate students who talked about their understanding of human blood circulation revealed problems understanding the blood circulation pathway, gas exchange, gas transport, and lung function (9). These errors were revealed when the learning environment encouraged students to verbalize their ideas. Modell et al. (7) found that in physiology laboratories, students performed best when they were required to make verbal predictions with an instructor who was available to discuss the results of their investigation. Clearly, opportunities for student involvement and teacher support during laboratory instruction contribute to an effective learning environment.
Although an effective learning environment reveals misconceptions that students hold about circulation, it does not explain why they hold misconceptions. A study (3) about what young children think happens inside their bodies provides insight into why students have difficulty understanding human blood circulation. Understanding the circulatory system is difficult since it is a complex organ system that is made up of tissue and cellular structures that are too small to be seen without the aid of a microscope. Students do not always have the opportunity to visualize the functioning of the circulatory system and to understand how it interacts with other systems in the body. Carey (4) reported that even though the heart is the first organ students recognize, they have little knowledge of its function and its relationship to the lungs. Mintzes (6) found that children have naïve conceptions about the function of the circulatory system. For example, young children think the heart produces and even cleans blood, while older children associate the heart with breathing.
Little research has been done to detect high school students understanding of blood transport or the function of the cardiovascular system. Nearly all students in the United States are required to take a high school biology course. Most have daily contact with a teacher and a weekly biology laboratory, so high school biology presents the first chance (and for many students, their only chance) to observe functions like blood circulation in animals. According to America's Lab Report (8), most high schools use textbooks and laboratory manuals from publishers that have not been designed or refined on the basis of education research. Therefore, for this study, an inquiry-based laboratory approach was used to give high school students an opportunity to observe blood circulation in live animals and to investigate how the cardiovascular system works. Since many high school students bring misconceptions about blood circulation to the classroom, it was important to develop an instructional laboratory environment where students could explore their ideas and have the opportunity to change their incorrect ideas and thinking through biological investigations. Because the care and use of live organisms is expensive and not all schools have access to high-resolution microscopes or the funds needed to maintain the equipment, in this study we explored the effects when students investigated various organisms' blood circulation in digital video format compared with more traditional microscope investigations using actual live organisms. The focus of this study was on aspects of a high school biology laboratory learning environment that would help students learn how investigations can be conducted to answer puzzling questions about animal physiology.
Learning environment instruments have been developed to measure the dynamics of the classroom from the student's perspective that may not be possible by outside observation (5, 10). Assessment with these instruments can provide meaningful information about the perceived classroom environment, which may affect student learning outcomes. These instruments provide an avenue to examine what is going on in the classroom and provide teachers with insights into how their students perceive the classroom learning environment (11). When teachers are aware of students' perceptions of the classroom learning environment, they may be better able to help their students make sense of what they learn in science or about science as an enterprise (10).
To investigate and assess how students perceive their learning environment in this study, the "What Is Happening in this Class?" (WIHIC) questionnaire was used. The WIHIC questionnaire originally contained nine scales and was modified to its final version of seven scales after extensive field testing. The WIHIC questionnaire is available in two forms, which include a personal form that assesses the perception students have of their learning environment from an individual perspective and a class form that measures student perception in respect to the entire class (5). The WIHIC questionnaire detects students' perceptions of their learning environment with seven scales that measure student cohesiveness, teacher support, involvement, investigation, task orientation, cooperation, and equity (5). We hypothesized that there would be no difference in students' perceptions of their learning environments between those who used digital video compared with those who used microscopes to investigate blood circulation. The results indicated that the investigation dimension of the learning environment was affected when digital video resources were used instead of live organisms to investigate patterns of blood circulation.
METHODS
Participants.
In May 2003, a comparison study using digital video images (5 classes) and traditional laboratory instruction with microscopes (5 classes) was performed with grade 10 biology students. Three faculty members taught 259 biology students in a California high school with students from diverse ethnolinguistic groups who were divided into 5 classes using microscopes (128 students) and 5 classes using digital video (131 students) to compare blood transport among invertebrates, fish, and humans. One California high school was not representative of schools throughout the United States. There was a representation of Hispanic and Native American students, but there was an underrepresentation of Asian-American and African-American students (Table 1). However, both college prep and noncollege-bound students were included in the sample because 98% of the students in the required biology courses agreed to participate in this study. Only 20% of these students normally continue to a four-year college. All teachers in the study taught high school biology classes in both groups. Assignment of groups to either treatment was random but was limited based on teacher schedules and the classes they taught.
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Video was delivered with Video and Image Data Access (VIDA), a science image project on the internet. A VIDA project objective was to identify content areas where images can best support learning. The images were organized in a database that is shared for use in an inquiry approach. Digital video microscopy was used for this study to show blood circulation in the California blackworm, Lumbriculus variegatus (http://scied.fullerton.edu/VIDA/VIDAImages/U2M5Lumbriculus/Home.htm), Daphnia (http://scied.fullerton.edu/VIDA/VIDAImages/U2M5Daphnia/Home.htm), and the egg, embryo, and juvenile stages of zebrafish (http://scied.fullerton.edu/VIDA/VIDAImages/U2M5zebrafish/Home.htm and http://scied.fullerton.edu/VIDA/VIDAImages/U2M5zebrafish/T00002.html). From 2005 to 2007, the American Association for the Advancement of Sciences (AAAS) BiosciEdNet project provided funding for this project from National Science Foundation National Science Digital Library Award 0532797 to make the VIDA collection available online without charge at http://www.vidacollection.org. Digital material from this study is posted under National Science Educational Standards, Life Science 5–8, Structure and function in living systems, Levels of organization in biology, using the zebrafish as an example (Record ID 114). Laboratory investigations using the video images versus microscopes were done in classes where students worked individually but in small groups giving each other help as needed. Students independently completed the pre- and postinvestigation WIHIC surveys (1, 10).
Instruments.
The present study used the most recent class form of the WIHIC questionnaire, as shown in Table 2 (2). Student responses were based upon a Likert scale of 1–5 with responses of almost always, often, sometimes, seldom, and almost never (1). A sample item for each scale is shown in Table 2. The seven scales of the WIHIC instrument each contained 8 items and had a minimum score of 8 and a maximum score of 40 on each scale. If we consider 24 to be neutral, then a mean score >24 would be considered positive and a mean score <24 was a negative perception of the learning environment.
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to be 0.05. Analyses were performed with SigmaStat software for statistical data analysis and Microsoft Excel for visualization of the results. Graphs show mean scores on the WIHIC questionnaire for each scale with error bars representing 95% confidence intervals. RESULTS
Based on the means of the seven scales in the WIHIC instrument, Aldridge et al. (2) found that students in Australia (1,081 students, 13–15 yr old, in 50 science classes) and Taiwan (1,879 students, 13–15 yr old, in 25 biology and 25 physics classes) perceived greater levels of student cohesiveness, task orientation, cooperation, and equity and lower levels of teacher support, involvement, and investigation. Students in this study perceived levels similar to both countries, as shown in Table 3. If this analysis is applied to student scores on the WIHIC instrument after the instructional intervention of this study, students in the microscope and video groups ranked student cohesiveness, teacher support, task orientation, cooperation, and equity as positive, similar to the findings of studies conducted in Australia and Taiwan. These results suggest that students supported each other, that the teacher helped or showed interest in them, that they agreed it was important to complete and stay on task, cooperated, and that their teacher treated them equally. These findings were similar for Taiwan, Australia, and the microscope and video groups in this study. The investigation and involvement dimensions were ranked lowest of the seven scales in all comparison groups in this study. Involvement was negative for the microscope and video groups, similar to the Taiwan study. The investigation dimension was negative for the video group, indicating that students may have felt learning should not be based on using inquiry-based investigations, similar to the Australia and Taiwan studies, but was positive for the microscope group.
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In summary, after using video clips to investigate blood circulation, students in the video group held more positive perceptions of classroom cohesiveness, cooperation, and equity. No differences in student perceptions of teacher support, involvement, investigation, or task orientation were detected after video instruction. After using microscopes with live animals to investigate blood circulation, students held more positive perceptions of cohesiveness, involvement, investigation, and cooperation dimensions of their classroom. After instruction, students who investigated with microscopes held a more positive perception of the investigation dimension, suggesting that the use of microscopes had a clear effect on this perception of learning environment that was not detected with the video treatment (Fig. 3). A change to a positive perception of the investigation scale with microscopes is a notable accomplishment given previous reports of a slightly negative perception of this scale in both Australia and Taiwan (Table 2).
DISCUSSION
The WIHIC questionnaire revealed some interesting differences between the video and microscope teaching interventions. First, even though the investigation dimension was ranked lowest in both groups, a significant difference was detected for this dimension in the microscope group and between the two groups after instruction. The microscope group ranked the investigation dimension higher after the intervention, which may indicate that students perceived the laboratory activities with microscopes to be more inquiry based. Second, involvement and investigation dimensions showed a significant change for the microscope group but not for the video group. Finally, investigation about blood circulation was associated with an increase in the cooperation and student cohesiveness scores for both microscope and video investigation interventions. Taking into account social and cultural factors in addition to learning materials from the present research and previous studies, both intervention groups perceived the other scales of the WIHIC learning environment questionnaire in a manner similar to or more positive than those detected in other countries, such as Australia and Taiwan.
Practical recommendations.
Many schools lack resources such as microscopes or funds for microscope maintenance. Purchasing and maintaining the live organisms in this study was labor intensive and costly. Schools may have trouble repeating the work due to the cost and labor involved in obtaining and maintaining the equipment and live organisms. In the present study, where every student had a properly functioning microscope during the laboratory activities, there were few if any problems using the microscopes to view the live organisms. In contrast, some problems were encountered accessing the videos even on days when the school computer laboratory was scheduled for the blood circulation video investigations. In addition to occasional connection problems, many schools do not have the funding or facilities to access computer time for viewing the videos of the present study during the course of instruction. For both video and microscope investigations of blood circulation, even though time was allowed, few students who were absent for the laboratory activities actually did the makeup work.
This study is one of the first detailed examinations of the effect of various forms of laboratory investigation as students learn about blood transport at the secondary school level. Little or no research has focused on investigating students' perceptions using an inquiry-based approach to the understanding of blood transport. This is the first study to compare microscopes with digital video to make it possible for students to investigate blood circulation in live organisms. Quantitative methods using the WIHIC questionnaire suggest the need for design studies. Video was found to be as effective as using microscopes in helping students cooperate and collaborate in an inquiry-based laboratory environment; however, the inquiry could potentially be designed more carefully with scaffolds or prompts to challenge specific misconceptions students hold. Instruction could combine the involvement and investigative aspects of microscope use in a laboratory classroom with the more equitable discussions and access to information afforded by video resources.
Ways to improve instruction cannot always be determined through experimental investigations, such as the present research. Whether students inquired using video or microscopes did not make much difference. In both cases, from the students' perspective, they were involved and able to cooperate to support and help each other learn about blood circulation by doing investigations. The results clearly show that both methods contributed to the learning environment. With both methods, the students worked with shared norms and procedures and broad participation to experience the process of investigation. Furthermore, investigations with video clips could be useful since students who used digital video had no differences in their perceptions of student cohesiveness, teacher support, involvement, task orientation, cooperation, and equity compared with students who used microscopes to investigate blood circulation. However, students who used microscopes had a more positive perception of the investigation dimension of their learning environment than did students who used digital video to investigate blood circulation. Even if no differences were found in their learning about blood circulation, the results of this study suggest the need to evaluate how well students learn to investigate as an outcome of various modes of laboratory instruction. Methods to assess the quality of student investigations are needed.
Video does not replace microscope investigations. We do not claim that students learn more about blood circulation or how to investigate blood circulation with microscopes and live organisms compared with video investigations because these questions were not addressed in this study. Incorporating a series of gradual improvements in instructional design using both video and microscope instruction may help make laboratory investigation of blood circulation more efficient and effective. We are presently exploring what students actually learn from these investigative approaches.
GRANTS
This material is based in part upon work supported by the National Science Foundation under Course Curriculum and Laboratory Improvement Grant 0127164 and National Science Digital Library Grant 0532797.
DISCLAIMER
Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.
Acknowledgments
Thanks go to David F. Treagust, Curtin University of Technology, Science and Mathematics Education Centre, for the advice on this project and to the California high school teachers and students who agreed to participate in this study.
Present address of N. Pelaez: Dept. of Biological Sciences, Purdue Univ., West Lafayette, IN.
Received for publication February 12, 2007. Accepted for publication July 26, 2007.
REFERENCES
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