|Australasian Journal of Educational Technology
2011, 27(6), 979-996.
Implementing clickers to assist learning in science lectures: The Clicker-Assisted Conceptual Change model
Yi-Chun Lin, Tzu-Chien Liu and Ching-Chi Chu
National Central University, Taiwan
The purposes of this study were twofold. The first aim was to design and develop a clicker-based instructional model known as Clicker-Assisted Conceptual Change (CACC), based on the cognitive conflict approach for conceptual change, to help students to learn scientific concepts. The second aim was to determine the beneficial effects of CACC on students' scientific learning and to explore how CACC might achieve these benefits. Introductory physics was the learning subject, and a mixed-method embedded observation and interview methodology within a quasi-experimental design was used to address the second aim. The participants in this study were 275 first year undergraduates from 6 classes. One class was selected as the experimental group (50 first years) and the other 5 classes were selected as the comparison group (225 first years). The results show that the experimental group who used CACC performed significantly better in the comprehension test than did the comparison group, who used common instructional methods. However, the performance of the calculation test did not differ significantly between the two groups. Several benefits and challenges of CACC are used to explain these findings based on the observational and interview data. Finally, recommendations for future studies on the application of clickers are provided based on this work.
"Clickers" (also known as audience response systems, interactive response systems, or other names) is a general term for a tool that consists of a simple handheld signal transmitter, a signal receiver and related software (Liu, Liang, Wang & Chan, 2003; MacArthur & Jones, 2008). By using clickers, a teacher can show a multiple-choice question on a large display and all students can anonymously transmit their answers simultaneously. The teacher can then conveniently present all of the students' opinions in an efficient way, for example by displaying the frequencies of specific answers (Hancock, 2010; Kay & LeSage, 2009a, 2009b; Lantz, 2010). This provides clickers with great educational potential to promote student engagement in classroom activities (Draper & Brown, 2004) and enhance their learning performance (Campbell & Mayer, 2009; Mayer et al., 2009; Sharma, Khachan, Chan & O'Byrne, 2005) by enabling every student in a lecture class to share their opinions in a public but non-intimidating way (Beatty, 2004). However, introducing an innovative technology into the classroom does not automatically guarantee that the associated educational benefits will be realised (Liu, 2007). Some studies have shown that the application of clickers does not contribute to better learning performance than does other types of instruction (e.g. Bunce, VandenPlas & Havanki, 2006; Paschal, 2002). Indeed, the review study of MacArthur and Jones (2008) showed that applying clickers in an inappropriate way (e.g. teachers using them primarily as a tool for taking attendance records and for assessments) may result in students developing a negative attitude towards clicker-based instruction.
The review study by Lantz (2010) found that principles which could enhance the effects of clicker-based instruction are needed, but these are currently still lacking. Therefore, designing and developing a suitable clicker-based instructional model to promote the potential benefits of clickers and hence help teachers achieve their difficult mission is seen as an important research issue (Woelk, 2008).
In science education, enhancing conceptual change among students is an important but difficult task (Limon, 2001), and the cognitive conflict approach is often used to achieve this change (Chan, Burtis & Bereiter, 1997; Limon, 2001). Lee and Kwon (2001) integrated many definitions of cognitive conflict and ultimately defined it as a perceptual state in which one feels that one's cognitive structure is inconsistent with external information, or one finds that there are some contradictions between the constituents of one's cognitive structure.
In order to promote students' conceptual change by way of cognitive conflict, teachers should teach with several important principles, including the elicitation of students' existing concepts, the presentation of contradictory information, the evaluation of students' conceptual change and the promotion of student motivation (Limon, 2001; Vosniadou & Vamvakoussi, 2006). Although some of these principles have been used to develop the environment for individual learning (e.g. Liu, 2010), they are very difficult to apply in the large class situation. The potential educational benefits of clickers, such as providing students with opportunities to share their opinions (Beatty, 2004), enhancing classroom interactions (Siau, Sheng & Nah, 2006) and promoting student engagement (Draper & Brown, 2004), may help teachers to teach effectively with the principles necessary for cognitive conflict. Therefore, the first aim of the current study was to develop a clicker-based instructional model, known as Clicker-Assisted Conceptual Change (CACC), to benefit students' understanding of scientific concepts in the university setting. This model combines the potential educational benefits of clickers and the critical principles needed to elicit conceptual changes using the cognitive conflict approach.
In addition, although several empirical studies have explored the impact of the introduction of clickers into classrooms and provided useful practical suggestions, more empirical studies are needed to further prove the effects of the application of this technology (Mayer et al., 2009). Kay and LeSage (2009a) reviewed 67 peer-reviewed papers on the application of clickers, and reported several limitations of the study methodologies used to investigate the effects of this approach. For example, most studies have focused on exploring students' attitudes towards clickers, while few have focused on exploring students' learning performances. Furthermore, most studies have used qualitative methods, with few having used quantitative methods. In recent years, the mixed-methods approach (Creswell & Plano Clark, 2007) has been accepted as a useful approach for examining the effects of technology-based instruction and exploring how the proposed effects can be achieved (e.g. Liu, Lin & Kinshuk, 2010; Sung, Chang, Lee &Yu, 2008). Therefore, the second aim of the current study was to use a mixed-methods approach to determine the effects of CACC on students' learning performance, and to explain the mechanisms underlying the presence or absence of such effects
In universities, introductory physics is considered an important subject and the necessary foundation for the learning of more advanced science, especially for undergraduates who plan to major in science or engineering. However, it is difficult to ensure that students understand the physics concepts presented in such courses (Perkins et al., 2006). Introductory physics was thus considered a relevant subject choice for examining the effects of CACC in science education.
This article introduces the principles for conceptual change by way of cognitive conflict and the corresponding methods for addressing these principles, and discusses the difficulties that may be confronted when using these methods. The CACC, the research questions and the methods used in the current study are detailed, and the findings are reported and discussed. Finally, the limitations of the current work and recommendations for future studies are outlined.
While these principles and corresponding methods may enable conceptual change among students, many obstacles may hinder their effectiveness, especially in large classroom situations. For example, the questioning method is important for addressing two principles necessary for cognitive conflict: (1) eliciting the students' existing concepts and promoting their awareness thereof, and (2) evaluating the degree of conceptual change among the students after instruction. However, it is difficult to apply the questioning method in lecture classes, especially those with a large number of students (Campbell & Mayer, 2009; Mayer et al., 2009).
Clickers, which have many functions (e.g. providing every student in a class with the opportunity to respond to a question at the same time, computing all of the students' responses and instantly displaying their distributions), have the potential to help teachers to overcome the obstacles that they may encounter when attempting to use cognitive conflict to enable conceptual change. For example, one benefit of clickers is that they can increase students' motivation to engage in the learning activity (Kay & LeSage, 2009a), which is critical for cognitive conflict. The next section introduces the clicker-based instructional model for conceptual change via the cognitive conflict approach.
Figure 1: The Clicker-Assisted Conceptual Change (CACC) model
the method in a
|Elicit students' existing concepts and promote their awareness thereof||Maintain students' motivation to engage in learning in all phases of CACC||Questioning method||Few students can respond to the question and only one student can respond at any one time.||All students can provide their responses anonymously and simultaneously so that everyone can immediately view the opinions of the entire class.|
|Facilitation-Reflection||Present students with contradictory information and ask them to reflect on it||Scientific demonstr-|
ations and discussions
|It is difficult to motivate most students to observe scientific demonstrations and participate in the related discussions.||Students can become more involved in observing scientific demonstrations and participating in the related discussions for knowing the answer to the questions presented in the earlier phase.|
|Guidance-Restructure||Provide students with sufficient knowledge to make them better understand the concepts||Lectures and guidance||It is difficult to motivate most students sufficiently to pay attention to the lecture.||Students would pay attention to the contents of the lecture in order to address their cognitive conflict resulted from the contradictions between their existing knowledge and the demonstrated concepts.|
|Evaluation-Elaboration||Evaluate degree of conceptual change among the students' and have them elaborate on their concepts||Questioning method||Few students can respond to the question and only one student can respond at any one time.||All students can provide their responses anonymously and simultaneously; the teacher can thus determine whether or not the students have achieved the conceptual change.|
Only one class was used as the experimental group because the teacher for this group needed to be willing to have his or her classes observed for 9 weeks. Moreover, because CACC is an innovative instructional model, the teacher had to devote time to becoming sufficiently familiar with its application before the intervention in order to be able to apply it smoothly. Consequently, the teacher selected for the experimental group was a member of our research group who had previous experience teaching physics with clickers. Five classes were selected as the comparison group in order to represent various instructions used in university class settings.
|Comprehension test||Calculation test|
In order to control for factors that might have affected the post-test score of this study, apart from the "instructional method", the learning time and learning contents of the two groups were controlled so that they were as similar as possible. For example, the two groups carried out different instructional methods twice weekly (2 hours for each session, 4 hours total) and both groups received a 9-week introductory physics course about "mechanical energy", "work" and "rotation". Moreover, in order to confirm that the two groups were provided with similar learning contents, the teachers participating in this study discussed the teaching schedule for the entire course 3 weeks before the intervention.
Figure 2: Evaluation procedure for the study
|Experimental group||Comparison group|
In CACC, the questioning method (along with the clickers) that was used in the first phase (elicitation-externalisation) is considered a catalyst for engaging the entire class, encouraging all of the students to begin thinking about important concepts, which is often a considerable challenge in traditional classes. In this phase, all of the students were encouraged to think about the questions and then asked to individually express their answers using the clickers. After all of the students' responses were aggregated into a bar chart that showed clearly the distribution of the answers, the teacher asked the students to provide reasons for specific answers. In this way, the students appeared to be separable into several groups according to their choices, and each such group had a sense of commitment to its response (Roschelle & Pea, 2002). This commitment leads students to play a more active role in the subsequent phases of the process in order to determine whether their answers were correct or incorrect, hence becoming more engaged in thinking about the concept to be learned.
In the experimental group of the current study, the questioning method (along with the clickers) was moderately used (3 to 5 times) in each course depending on the teacher's need. The interview data revealed that the students enjoyed this method and thought that the questioning and answering process could facilitate their engagement in the subsequent learning activities (e.g. I02, I12 and I41). For example, I12 stated: "I like the questioning and answering activity... that tool (transmitter) gives me more opportunity to express my ideas... After I give my answer, I always eagerly want to know if my answer is right or wrong... I think that feeling makes me more involved in the class".
After students' existing concepts had been externalised in the earlier phase and the curiosity to know the correct concept is stimulated, the teacher used the "seeing is believing" method by presenting a demonstration during the demonstration-reflection phase to provide students with opportunities to find the correct answers. Observational records and interview data showed that this can retain or even prolong the engagement of students who were already engaged in the learning process, thus providing them with more opportunities to enhance the occurrence of cognitive conflict.
For example, according to the observational records, when the teacher began to conduct the demonstration, most students rushed to the front of the classroom in order to be able to observe it more closely. Moreover, when the results appeared to be in conflict with their current ideas, most of the students were surprised. The interview data also support the observational data. For example, I17 noted: "... and you should observe the results of the demonstration... It is clear that I felt surprise when what I observed was different from what I thought... I would focus more on why these results happened during the lecture that followed".
Some studies have shown that applying clickers can motivate students to think more deeply about important concepts (Draper & Brown, 2004; Greer & Heaney, 2004); this was also supported by the findings of the current study. The interview data revealed that in the elicitation-externalisation and evaluation-elaboration phases of the CACC model, the students were forced to think through their responses carefully because they knew that their answers would be presented on the large display, and that they could be picked to express the reasoning behind their responses. For example, I43 stated that "The main difference between this course (introductory physics) and other courses is that I need to make a lot of effort thinking throughout the whole course... I cannot casually select an answer to the question because it would be embarrassing if I cannot give a reasonable explanation for the answer when I am selected (by the teacher)".
Moreover, the interview results echoed other study results indicating that the use of clickers in the questioning method may increase pressure on students (e.g. Kay & LeSage, 2009a; MacArthur & Jones, 2008). For example, I33 noted that "Actually, the use of this model makes the course more interesting, but it also makes me feel more pressure in learning... Because, after giving the response with the clicker, I am always afraid of being selected by the teacher to express my ideas."
Finally, the interview data showed that several students (e.g. I03 and I05) were unhappy in the class and expressed negative attitudes towards CACC. These students responded that they preferred the traditional instructional model to CACC because the traditional approach focuses on explanations of the formulas, which allows them to solve problems more rapidly. For example, I05 stated that "Not everyone likes a course with more interaction between the teacher and students... I hope the teacher can spend more time on introducing and explaining the formulas that will be of more benefit when taking exams." Such doubts and negative perceptions towards CACC should be considered in future revisions and applications of the CACC model.
Cognitive conflict is a useful approach for promoting conceptual change, which is an important task in science education (Chan et al., 1997; Limon, 2001). However, it is very difficult to implement in lecture classes. With the assistance of clickers, it is assumed that application of the CACC model can address some important but challenging principles for cognitive conflict in lecture classes and can benefit the students' understanding of physics concepts. The results of this study support the assumption that physics comprehension is benefited more by CACC than by the instructional methods used in the comparison group. The findings from direct observation and interviews also revealed that most students felt that the application of CACC allows them to retain and prolong their engagement in the course content, and stimulate them to think more deeply about important concepts.
While these results show that the CACC model has the potential to benefit students' understanding of physics concepts, we also found that its implementation did not significantly improve students' performance of physics calculations, relative to that of the comparison group. Furthermore, the interview data from some of the students also raised some concerns regarding this method, such as course coverage, the pressure associated with the questioning method and the negative attitudes towards a new style of instruction.
Based on the results of this study, we recommend the following guidelines for future applications and research. First, other key science topics should be used as the learning focus of the CACC model to test the benefits of this instructional model (if any) in different contexts. Furthermore, since some students had concerns about time shortages and anxiety when using the model, future work could revise the CACC procedure such as by rearranging the contents of the course and changing the method used to ask questions in class. Finally, in order to better understand the full potential of clickers (Woelk, 2008), more clicker functions could be explored in conjunction with various learning theories. Subsequently, various instructional models could be constructed and examined using a mixed-method approach.
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The facilitation - reflection phase
After the end of the discussion in the earlier phase, and in order to foster cognitive conflict in students with the incorrect concepts or confirm the ideas of those with the right answers, the teacher shows a computer simulation that shows two bodies, one of which is a slender rod with length and the other a simple pendulum with the same length L (i.e., the same situation as in the question used in the elicitation phase). Before playing the simulation, the teacher repeats the question from the earlier phase and reminds the students to carefully observe the simulation. The teacher then asks all of the students to confirm that the length and mass of the two bodies are the same. The teacher plays the simulation three times and asks the students "Does the result agree with your choice in the earlier phase? Why or why not?" After using the computer simulation, the teacher asks several questions to lead students to think about the differences between the results of the simulation and their ideas, such as: "What do you think based on your observations?" "What are the reasons for the results? And please try to explain them." The teacher then selects students who provided wrong responses to the question in the elicitation phase.
The guidance - restructure phase
After a discussion about the differences between the students' responses and the results of the simulation, the teacher presents the learning contents related to "Simple Harmonic Oscillation" and "Moment of Inertia" using a PowerPoint presentation to provide students with a more structured and clearer understanding of these concepts. After the lecture, the teacher leads students to think about the reasons for the results of the simulation in the earlier phase of the lecture.
The evaluation - elaboration phase
Finally, to confirm whether most of the students have understood the concepts correctly, the teacher presents an advanced question on the large display, as follows: "What is the length ratio of the rod and simple pendulum that results in a same-period oscillation?" The students are also asked to answer this question using their handheld transmitters, and the teacher shows the correct answer and the distribution of answers. If most students provide the correct response, the teacher continues to the next topic; if not, the teacher returns to the earlier phase to introduce and explain the main concepts again.
|A yo-yo is initially at rest on a horizontal surface. A string is pulled in the direction shown in the figure. Assume there is sufficient friction for the yo-yo to roll without slipping. In what direction will the yo-yo rotate and move?
(A) Move to the right with no rotation
(B) Move to the left and rotate anticlockwise
(C) Move to the left and rotate clockwise
(D) Move to the right and rotate clockwise
(E) Move to the right and rotate anticlockwise*
An example item from the calculation test (* indicates the correct answer):
|An object of mass 5.0 kg is moving with a speed of 20 m/s. How much work is required to make the object reach a final speed of 40 m/s?
(A) 750 J
(B) 1000 J
(C) 1500 J
(D) 3000 J*
(E) 8000 J
|Authors: Yi-Chun Lin, PhD candidate, Graduate Institute of Learning & Instruction, National Central University, Taoyuan, Taiwan. Email: email@example.com
Dr Tzu-Chien Liu (corresponding author), Professor and Director, Graduate Institute of Learning & Instruction, National Central University, Taoyuan, Taiwan. Email: firstname.lastname@example.org
Dr Ching-Chi Chu, Assistant professor, Department of Physics, National Central University, Taoyuan, Taiwan. Email: email@example.com
Please cite as: Lin, Y.-C., Liu, T.-C. & Chu, C.-C. (2011). Implementing clickers to assist learning in science lectures: The Clicker-Assisted Conceptual Change model. Australasian Journal of Educational Technology, 27(6), 979-996. http://www.ascilite.org.au/ajet/ajet27/lin.html