Using Self-Reflection To Increase Science Process ... - ACS Publications

Research: Science and Education edited by

Chemical Education Research

Diane M. Bunce The Catholic University of America Washington, DC 20064

Michael J. Sanger Middle Tennessee State University Murfreesboro, TN 37132

Using Self-Reflection To Increase Science Process Skills in the General Chemistry Laboratory William R. Veal* Department of Teacher Education, College of Charleston, Charleston, SC 29424; *[email protected] Dawne Taylor and Amy L. Rogers Department of Chemistry and Biochemistry, College of Charleston, Charleston, SC 29424

Students in general chemistry constantly struggle with the development of knowledge and skills. The laboratory setting should be an extension of the knowledge learned in lecture with the added benefit of applying the knowledge in a hands-on, minds-on manner in which students must learn and use process skills to solve problems and complete laboratory exercises. Many chemistry laboratory courses have teaching assistants or instructors demonstrating, showing, telling, and modeling different process skills that will help students complete the laboratory exercise. The purpose of this study was to determine the effect of student self-reflection, using immediate videotape feedback and direct instruction, on the development of certain process skills of general chemistry students at the university level. Students in one undergraduate, general chemistry laboratory course for nonmajors reflected on their laboratory process skills by viewing themselves completing certain tasks and receiving personalized instructor feedback. The other set of students was used as a control group and was not urged to self-reflect on their skills during their laboratory course. Students in the experimental group reflected on their actions, received instructor feedback, answered a survey, and were interviewed. Both the control and experimental groups of students were assessed using the same pre- and postlab quiz questions, a standardized end of course exam, and an end of course laboratory practical exam. Contextualizing Self-Reflection and Process Skills Self-reflection or reflective practice is the process by which a person reflects on his or her actions in a deliberate or nondeliberate manner, either immediately or after some time, in order to think critically about what has been done (1–2). This practice “is intended to hone the reflective capabilities of observation, analysis, interpretation, and decision making” (3). In teacher education, many programs for teachers have adopted the reflective practitioner model as a way to make teachers critically analyze their actions in a classroom (3). Along similar lines, science educators have adopted the idea that they should ask questions about the science learning they facilitate and systematically seek answers as directed in the National Science Education Standards (4–5). In chemistry, reflection has been used by high school chemistry teachers to reflect on the implementation of inquiry

teaching methods in a high school context (6). At the college level, reflection coupled with a “diagnostic learning log” has been used to focus science nonmajors on how they learn best (7). Videotapes, video, and film have been used as a multimedia tool in teaching for many decades. How these tools have been implemented and in which content courses they were used have differed based upon the availability of the tools, the desire of the instructor, and or the application of the technology. Videotaping has been used to demonstrate laboratory procedures in general chemistry (8), organic chemistry (9–10), inorganic chemistry (11), and physical chemistry (12). Videotapes have helped to further explain methods for calculating standard additions (13) and to introduce laboratory techniques for upper-level analytical chemistry courses (14). Video has been used to explore the critical self-reflection of preservice teachers to help them understand their practical teaching knowledge (15–18). Research has provided a sound foundation for using video to reflect on actions, whether in a classroom or in the field (19). Some research exists on the use of “instant video” to reflect on actions (20). The use of video to promote self-reflection has not been applied to students in chemistry classes at the university level. Process skills are an important aspect of learning science. Padilla (21) stated that process skills are a “set of broadly transferable abilities, appropriate to many science disciplines and reflective of the behavior of scientists”. Science as a content area contains a body of knowledge, a knowledge of process, and a way of knowing. Process skills are necessary for individuals to learn the process of science and they help individuals contextualize the body of knowledge. Martin (22) has stated, “Process skills form the core of inquiry-based, hands-on science learning”. He has classified process skills into two categories: basic and integrated. The basic skills include observing, classifying, communicating, measuring, predicting, and inferring. The integrated skills include identifying and controlling variables, formulating and testing hypotheses, interpreting data, defining operationally, experimenting, and constructing models. Rationale Based on years of personal experience teaching chemistry, we determined that general chemistry students needed to learn

© Division of Chemical Education • www.JCE.DivCHED.org • Vol. 86 No. 3 March 2009 • Journal of Chemical Education

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Research: Science and Education Table 1. Sample Process Skill Quiz Questions Process Skill

Sample Quiz Question

Observation (Before)

You have an unknown compound that contains either a sodium or potassium cation. What would you do in order to determine which cation it was and what would you be looking for?

Observation (After)

When testing for particles in solution such as Cl−, why is it important to first run a series of tests with known solutions containing the ions?

Measuring

Where would you read a volume of a liquid in a graduated cylinder?

Lighting a Bunsen Burner

Abigail lights her Bunsen burner and her flame is very high and yellow. She turns to you and asks frantically what she should do. What do you tell her?

Communicating

Using a complete sentence, explain why is it better to use a hot plate versus a Bunsen burner when heating a water bath.

Pipetting

How can you avoid getting bubbles in a solution while pipetting it out of a beaker?

Titrating

Determine the percent (m/v) of vinegar in the solution you pipetted in the previous question or station. Use the titration setup to determine the amount (in mL) of titrating solution needed to neutralize the vinegar solution.

certain process skills better in order to succeed on laboratory exercises. After a review of all of the laboratory exercises in the laboratory manual, six process skills were determined to be important if the students were to succeed in this laboratory course: lighting a Bunsen burner, measuring, observing, communicating, pipetting, and titrating. These skills were then divided into categories (basic and integrated) established by Martin. The basic processes that agreed with Martin’s designation were observing, communicating, and measuring. Integrated process skills as defined by Martin were not evaluated; rather a separate category of advanced skills was developed. Three process skills were considered advanced by the researchers; lighting a Bunsen burner, pipetting, and titrating. Advanced skills were defined as those skills that used more than one basic skill at the same time to ensure that accurate data were collected and a laboratory procedure could proceed. Methods We implemented a nonequivalent, control group, quasiexperimental design to measure the effects of self-reflection using video feedback on the mastery of basic and advanced process skills in the general chemistry curriculum (23). This study used a mixture of qualitative and quantitative methods (24) to answer the research question: How does the promotion of self-reflection on process skills through personalized instructor feedback and videotape self-reflection affect the development of process skills and laboratory achievement? Qualitatively, the research question was addressed by interviewing the subjects, conducting a survey of the subjects, and analyzing videotape of students reflecting while watching themselves perform specific process skills. Quantitatively, different statistical tests such as t tests and one-way analysis of variance (ANOVA) were used to measure the effect of self-reflection on student process skills and content knowledge using quiz and test data. General Chemistry Laboratory A general chemistry laboratory course for nonmajors was used as the context for this study. The chemistry course

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covered the major concepts and content of general inorganic and physical chemistry using a popular textbook (25) at the first-year college level. The course was designed to meet the requirements for nonscience majors as well as those entering an allied health field, such as nursing. Students were also enrolled in this course to prepare for the more intense two-semester general chemistry curriculum required for all science majors. This course focused on basic chemistry concepts, including atomic structure, chemical bonding, molecular reactions and stoichiometry, solutions, kinetics, equilibria, and nuclear chemistry. Once students completed this course they should have had a greater appreciation for the role of science, particularly chemistry, in their day-to-day life. Participants and Procedure Students were divided into an experimental group and a control group. The mastery of the process skills in question were evaluated through weekly quizzes, students’ performance on a laboratory practical final exam, and final grades in both the lecture and laboratory component of the course. One of the authors taught one section of the general chemistry course and laboratory with 17 students in the summer of 2006 (experimental group). Another author taught two laboratory sections with 39 students in the fall semester of 2006 in which students had different lecture professors (control group). The students in the summer course—who volunteered to be part of the study—served as the experimental group and were videotaped during different laboratories completing certain tasks and skills by one of the authors serving as the videographer. For three of the process skills (measuring, lighting a Bunsen burner, and using a pipette) students were asked one by one to come to a secluded area of the lab and perform a task related to one of the three process skills. The task and process skill were directly related to the laboratory exercises for that day. For the other three process skills (observing, communicating, and titrating) students were videotaped while performing a laboratory exercise. During their videotaped performance of the process skill, students were asked to verbally explain what they were doing. Immediately following the task, the videog-

Journal of Chemical Education • Vol. 86 No. 3 March 2009 • www.JCE.DivCHED.org • © Division of Chemical Education

Research: Science and Education Table 2. Comparison of Experimental and Control Group Responses on Process Skill Question Scores Process Skill

Experimental Group Mean Score

Control Group Mean Score

Experimental Group Standard Deviation

Control Group Standard Deviation

Measuring—After

3.6

2.8

1.5

1.1

Observing—Before

14.9

15.0

2.0

2.7

Observing—After

29.4

27.3

2.2

2.6

Communicating—After

1.6

1.9

0.9

0.7

Bunsen Burner—Before

7.8

7.7

0.4

1.3

Bunsen Burner—After

6.5

5.1

1.4

1.7

Pipetting—After

3.0

2.4

1.0

1.0

Titrating—After

11.2

11.0

2.2

2.0

N.B. Values displayed in bold type indicate a statistically significant result at the 95% confidence level in which students in the experimental group outperformed students in the control group on certain process skill questions.

rapher asked the students to self-reflect on their performance, how they completed the task, and what may have gone correctly or incorrectly. These open-ended questions allowed the students to reflect on their actions and evaluate their actions and abilities to complete the task. Personalized and direct instruction ensued with the videographer showing the students their performance from the videotape on the video recorder. Minimal instructional guidance and suggestions were made to correct any process skill errors and tasks. Both the experimental and control groups conducted the same laboratory exercises, covered the same lecture material, took the same laboratory quizzes, completed the same standardized final exam, and finished the same laboratory practical exam. Only the experimental group was urged to self-reflect using the videotape of their performance. The experimental group was also interviewed and completed a survey. Data Sources and Instruments A variety of instruments was used to collect data for this study. Content questions related to the six process skills were developed and inserted into laboratory quizzes and the laboratory practical exam. An interview protocol was used to interview students at the end of the course. A survey with Likert-scale responses was conducted to measure the effect of self-reflection using immediate videotape instruction and feedback in the lab. Once the set of process skills was determined for the laboratory exercises, a set of questions were developed for each process skill. These questions were inserted into the laboratory quizzes and were coded based on whether the question was asking the student prior to or after receiving the videotape feedback in laboratory class. Both groups of students received the same questions. The treatment group, for example, was given questions for the “observing” process skill before and after self-reflection. Only one basic and one advanced process skill—observing and Bunsen burner, respectively—were evaluated on a pre and post basis. The other four process skills were evaluated after videotape intervention. Table 1 shows a sample of the questions used on the quizzes for each process skill. The hands-on laboratory practical contained

traditional content questions relating to the chemistry content of the lab exercises and hands-on tasks to be completed. For example, students had to determine the specific heat of an unknown metal at one laboratory station. This task highlighted observing, measuring, and lighting a Bunsen burner process skills. The interview protocol included questions asking students to reflect on the laboratory exercises and their opinions on the immediate feedback from the videotape. For example, the questions relating to the videotape feedback were: How did the immediate video feedback help you develop certain laboratory process skills? and How did viewing your procedure help you learn the content of the laboratories? Using a Likert scale for responses, the survey had 15 items divided into three categories: videotape reflection, laboratory experiments, and lecture. The videotape reflection questions focused on how the feedback helped the student understand errors in technique, chemistry concepts, lecture material, mathematical processes, and practical applications of the content. The laboratory experiment questions focused on how the laboratory experiments helped students understand the lecture material, practical applications, mathematical processes, importance of proper technique, and proper laboratory techniques. The lecture questions focused on how the lecture helped students understand the importance of proper laboratory techniques, chemical concepts, chemistry processes, practical applications of chemistry, and mathematical processes. Results Both qualitative and quantitative analyses were conducted to answer the research question. Quantitative data, quiz scores, and Likert-scale responses were entered into a spreadsheet and analyzed using SPSS version 10.0. A Levine test for significance was used to determine significance at the 95% confidence level for the t tests (24). A Bonferroni post hoc test was used for the one-way ANOVA of means from the survey results (24). The qualitative data were analyzed holistically to find themes. These themes were defined, combined, and refined into categories that related to the research question.


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Research: Science and Education

Achievement Data The laboratory quiz data for all participants were coded by quiz number and laboratory exercise number and then entered into a spreadsheet. For the null hypothesis we posited that no difference existed between the quiz scores for the experimental group and the control group. A t test was run to compare the mean achievement on the quiz questions for each process skill and then for the total score for the pre and post mean for each process skill. The analysis separated observation and Bunsen burner skills into before and after achievement. Analysis of measuring, communicating, pipetting, and titrating were only done after the process skill was learned or performed in the lab. Table 2 shows the means and standard deviations on the comparison of total scores for all questions related to the process skills from the different quizzes. The t test for equality of means assuming equal variances indicated that observation skills after (t = 2.728; p = 0.009), Bunsen burner after (t = 2.957, p = 0.005), and pipetting (t = 2.258, p = 0.028) were significantly different for the two groups. The decrease in scores for the Bunsen burner does not indicate a decrease in ability to complete the process skill because the total number of points possible on the preassessment and postassessment are different. These results indicate that those students who self-reflected on their performance after being videotaped increased their achievement and understanding of observing, lighting a Bunsen burner, and pipetting. For example, students in the experimental group scored higher than students in the control group on questions related to making proper observations after self-reflecting. Course grades and exams were also used to compare the effectiveness of self-reflection on student achievement. For the null hypothesis we postulated that the mean achievement on the laboratory practical exam, grades in laboratory and lecture, and standardized final exam scores were equal between the experimental and control groups. Scores on the American Chemical Society final for the course and the laboratory practical exam and grades in the lecture and laboratory were compared between the control and experimental groups. The t test for equality of means indicated that only the scores on the laboratory practical exam were statistically significant (t = 2.635, p = 0.011). This result indicates that hands-on performance on the laboratory practical exam was enhanced by the promotion of self-reflection on student performance of process skills using the videotape. The application to learning course content through self-reflection on process skills was not found. This result is not surprising because the students were not asked to reflect on concepts, but rather to reflect on skills that improve. This supports a disconnection often found between laboratory and lecture. Although the statistically significant results in this section indicate that there are differences between the two groups of students, additional corroborating data would make us more confident that these differences are real. These statistical results are supported by the analysis of the qualitative data in an effort to triangulate the conclusion that self-reflection aids in the development of process skills.

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Survey We analyzed the survey data using content analysis based on instructional method and a priori themes. The a priori themes were developed based on literature indicating what content knowledge and process skills students should know and be able to do (5, 21–22). The four a priori themes are increased understanding of laboratory technique, chemistry content knowledge, practical applications, and mathematical processes. Two other questions focused on reflecting on students’ process skills. The instructional methods included videotape feedback, laboratory experiences, and lecture for understanding science content. The responses were summed for each theme and instructional method. A one-way ANOVA was used to test the null hypothesis that each type of understanding was equal and that each type of instructional method was equal. Post-hoc analyses were run for each test to determine any significant differences among themes and instructional methods in the results. Themes The results of the survey indicate that the students strongly agreed that they understood process skills better than mathematical processes as a result of completing the laboratory course (F = 3.553, p = 0.020). For the null hypothesis we posited that the themes were considered equally important as a result of self-reflection in learning process skills. No significant differences existed between students’ perceptions of understanding chemistry concepts and practical applications with mathematical processes. No significant differences existed among understanding process skills, concepts, and practical applications. This result indicates that self-reflection on process skills aided the development of hands-on, tactile skills over a traditional cognitive skill. Instructional Method The results of the survey indicate that the students strongly agreed that self-reflection and lecture, as instructional methods, helped them understand process skills, concepts, practical applications, and mathematical processes better than the laboratory experience (F = 16.684, p = 0.000). For the null hypothesis we premised that the instructional methods were considered equally important as a result of self-reflection in learning process skills. No significant difference was found between self-reflection and lecture in understanding these concepts and processes. This result indicates that self-reflection on process skills helped students understand hands-on skills, application of these skills, and related cognitive skills. Self-Reflection on Process Skills Tasks Analysis of videotape segments of students self-reflecting on their performance of process skills indicated that students realized what they were doing properly and incorrectly. No difference was found in the type of process skill, basic or advanced. Three themes emerged from the transcribed data. First, all of the comments by students watching themselves perform the process skills were positive, and that the viewing and selfreflection on their performance were beneficial. For example,



one student commented, “I am a hands-on person and I have to do it whether I do it right or not. I would have probably never noticed that I held it with that hand.” Second, safety concerns were made more apparent and personal for students. Students were able to specifically state any potential hazardous procedures or actions when completing the process skills. For example, one student observing herself lighting a Bunsen burner stated, “I paid more attention to safety.” Third, the students overwhelmingly stated that viewing themselves perform these various tasks helped them critically analyze what they were doing procedurally. The procedural attention focused on the student doing the proper technique and completing the process. For example, one student, while observing himself pipette, stated, “I should have done a fuller squeeze there because I had to do it again.” Also, it is interesting to note that having students self-reflect on their performance and answer open ended questions aided in their use and understanding of the vocabulary associated with a general chemistry laboratory. Ultimately, the self-reflection on the videotape drew attention to students’ process skills more quickly and critically. Interview The interview data reflect a positive result from using selfreflection as a tool for developing science process skills. The main theme from the interview data was the immediate positive impact of self-reflection on performing the laboratory exercise with the proper process skill. When asked whether the immediate video feedback helped to develop laboratory process skills, the students unanimously responded that watching the video helped them to see what they were doing wrong during the laboratory procedure. One student responded, that “[T]he video feedback definitely helped develop laboratory process skills such as lighting a Bunsen burner, pipetting, and using a buret—mostly by allowing me to see what I was doing as compared to how I had learned the procedure, which was sometimes not quite exactly in line.” Some voiced that the visual self-reflection brought awareness of imperfect laboratory technique, while others commented on the effectiveness of discovering technical mistakes for themselves rather than an instructor abstractly describing the procedural error. A representative student response was that “[T]he immediate video feedback helped me develop certain lab process skills with watching what I did wrong and someone correcting me. …I could see what I did wrong versus someone just telling me what I did wrong.” All responses gave overwhelming support to the value of self-critique. Although viewing their laboratory procedure helped in development of process skills, it did not seem to help students learn the content of the laboratory. One student responded that, “[V]iewing my procedure didn’t help that much in learning the content of the lab: like I said, I am more of a hands-on learner—unless I am constantly doing something that helps me retain it.” Most of their responses to this question indicated that the viewing and self-reflecting on the procedure helped them execute the lab procedure better, but none of the responses directly indicated that self-reflection of process skills provided content understanding of the laboratory.

Conclusions The results of this study suggest that self-reflection using videotape feedback on laboratory process skills helped students develop stronger process skills. Comparative analysis of the qualitative and quantitative data indicates that process skills increased while laboratory and lecture course content knowledge did not. Essentially, self-reflection using immediate instructional feedback of viewing performance increased student ability to perform chemistry in the laboratory as evidenced by the higher test scores on the laboratory practical. This indicates that the process skills were understood better, but there was not a direct relationship to understanding chemistry content. Reflection is a tool to use for developing students’ abilities to observe, critically analyze, interpret, and make decisions. In this study, all four aspects of self-reflection were accomplished. First, students were able to make immediate observations about their process skills by observing themselves on the videotape. Students were able to reflect on their hands-on abilities and understand the direct instruction better because the videotape made the learning more personal and practical to the student. As a result, students’ self-reflection actually resulted in less teacher instruction on process skills. The direct instruction offered by the instructor added a second layer of understanding to the learning. Guided questions from the instructor helped students to focus on their procedures and abilities. Students then had the opportunity to reflect more precisely on specific aspects of a process skill or procedure. The videotape allowed for specific feedback that would have been lost otherwise. If self-reflection occurred through only verbal methods, students would not have been able to critically analyze in-depth the particular nuances of a process skill. The results from the quiz data indicate that students were able to interpret and apply their process skill. For example, the treatment group scored better on the practical exam than the control group because of the ability to interpret the proper application of a particular process skill. Analysis of the videotapes showed the students studying their actions, reflecting, and then interpreting the results of their actions. The awareness of safety issues added to the impact self-reflection had on interpreting their actions. The laboratory practical exam was a good indicator of the degree to which these students were able to make decisions. The practical situation of applying the process skills to specific questions demonstrated decision making. In addition, these students were able to reflect-in-action rather than reflect-on-action (2). Reflection-in-action means that these students were able to immediately observe and critique their procedures rather than waiting some time. Decisions about the lab procedure were made such that the proper methods were retained. In many instances, students leave the laboratory and either do not think about their actions or reflect inaccurately about their actions. Results indicate that self-reflection on process skills helped students learn process skills. Self-reflection using videotape feedback is an excellent method that aids in the development of process skills, but it does not help in the learning of science content. Another result from the data analysis unrelated to process skill


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