Implementing active-learning in an international context: A study in introductory physics G. Zavala1 and C.H. Kautz2 1 Tecnologico de Monterrey, Monterrey, N.L. 64849, Mexico, genaro.zavala@itesm.mx Hamburg University of Technology, D-21071 Hamburg, Germany, kautz@tu-harburg.de 2 Abstract Active learning has become widely recognized as a desired strategy for teaching in engineering education. Many of the active-learning instructional materials have been developed in the US. Instructors in non-English speaking countries wanting to implement these materials therefore face the choice between (a) using the materials in the original English versions, and consequently teaching in a language other than their students’ native language; and (b) using translations into the local language. Two sets of implementations of a particular set of instructional materials for introductory physics form the context for our investigation, one in Mexico and the other in Germany. At each institution, we have collected and analyzed data from students in locallanguage courses and courses taught in English. Results from both institutions indicate that, on average, students using the materials in English perform better than those using a translation. In our effort to explain this result, we have identified several variables that affect student performance. These include instructor factors such as commitment to active learning, as well as student factors such as reasoning skills, English and native language proficiency, mathematical skills, and prior academic performance. In our report, we analyze and discuss the influence of each of these factors. Keywords: Active-learning, international context. introductory physics, student difficulties, misconceptions, 1. INTRODUCTION While active learning is becoming more widely recognized as a preferred mode of teaching in engineering education, instructional materials that use this approach effectively are still rare. Many of the materials that are available have been developed in English-speaking countries, most often the US. For institutions elsewhere, this situation raises the question if and how these resources could be used either (a) for instruction delivered in English to predominantly non-native speakers, or (b) for instruction delivered in the local language if the materials are used in translation. There has been little research, however, on whether such materials can successfully be implemented outside of English-speaking countries, and whether a translation may have any adverse effect. This question is of particular importance due to the more intensive use of verbal reasoning in active-learning conceptual teaching materials compared to traditional (formula-based) science and engineering instruction. 2. OUTLINE OF THE PAPER In the present paper we report on two sets of implementations of a particular set of instructional materials for introductory physics at a large private university in Mexico and a small public university in Germany. We first present the way we implemented the educational strategy at the two sites both in the original language and in translation. Then, we discuss the ongoing assessment of the materials in these implementations through multiple-choice tests and other instruments, including some of the analysis tools we are using to gain information about the students’ level of understanding after working through the materials. Finally, we present some results we have obtained in recent years, discuss them in terms of the different variables that are likely to affect the learning outcomes, and present some conclusions based on the data gathered. 3. IMPLEMENTATION Among the several active learning methodologies that have been developed in the last decade as a practical result of Physics Education Research, PER, Tutorials in Introductory Physics [1] shows three distinct advantages: a) it can easily be adapted to almost any kind of course structure since it covers the usual curriculum of introductory physics; b) it places little demands on classroom time, materials, human and financial resources; and c) literature reports [2] indicate that Tutorials represent one of the most effective teaching strategies for introductory physics. Tutorials in Introductory Physics are a set of paper and pencil activities, helped in a few cases with very simple laboratory equipment. The tutorial cycle (for each of the topics covered) consists of a pre-test, the Tutorial worksheet, and a set of homework problems. The first and the last are activities carried out by the students individually (and generally outside of the classroom) while the Tutorial is worked out in groups of 3 or 4 students during class time with the help of an instructor guiding them with a Socratic-style dialog. The teaching strategy can be summarized in three basic steps: eliciting the student’s ideas about the specific concepts involved, confronting these ideas with evidence provided by the Tutorial, and finally resolving the inconsistencies. The pre-tests serve mainly the first step, while the Tutorial worksheets cover the remaining two objectives [3]. The homework assignments are intended to help students strengthen and extend their understanding of the concepts considered in the Tutorials. The Tutorials were designed to be used as a complement to lectures, especially in large-enrolment courses that are common at many research universities in the US. (In this setting, the tutorial workshops often replace more traditional small-group “recitation” sessions in which problem solving is demonstrated to students by teaching assistants.) Adopting the Tutorials at institutions that do not follow this pattern of instruction often requires that an existing teaching format is found in which the Tutorials can be implemented. Moreover, implementations in other countries can pose additional challenges. These may include the question of the language of instruction, i.e., whether a translation to the local language is used or instruction in English is given to non-native speakers. Other issues pertain to how student performance is monitored and assessment is carried out. At Tecnologico de Monterrey (ITESM), introductory physics is taught in three separate semester-long courses, that cover mechanics in the first; hydrostatics and hydrodynamics, mechanical waves, and thermal physics in the second; and electricity and magnetism, as well as optics in the third course. All three courses are offered each semester, and at any time throughout the academic year, more than 1800 students are enrolled in total. The students are divided into lecture (and laboratory) sections of about 36 (and 18) students each. Every semester, two of the lecture sections of each course are taught in English for students who are enrolled in an International Program (IP) while for the others in a regular program (RP) the instruction is in Spanish. These sections have the same curriculum and the same strategies as the Spanish sections. Tutorial worksheets are used in the lecture and in the laboratory format, using English and Spanish, respectively, for the IP, and only Spanish for the RP students. A Spanish translation of the Tutorials [4] was published by a commercial publisher and has now been available for several years. At Hamburg University of Technology (TUHH), the Tutorials have been adopted for the physics instruction of students in General Engineering Science (GES) and in Electrical Engineering (ET = “Elektrotechnik”). The former take a one-semester physics course that covers mechanics as well as a brief introduction to thermal physics, oscillations and waves, and optics. As in most other first-year courses in the GES program, instruction is carried out in English. Students in Electrical Engineering take a two-semester physics course that covers mechanics and thermal physics in the first semester, and optics and an introduction to modern physics in the second semester. Instruction for the ET students, as in almost all courses that are part of this program, is in German. Since a German translation of the Tutorials is not yet commercially available, one of the authors (CK) has translated the worksheets that were included in the two-semester course. The existence of both courses at TUHH provides us with the opportunity to implement the Tutorials in both languages, mirroring the situation at ITESM. In a two-year pilot run, Tutorials in the German course were first done on a bi-weekly basis before adopting a weekly schedule as in the English course. 3.1 Pretests At ITESM, in a previous semester pretests were implemented as voluntary on-line but only 40% of both IP and RP students took the pre-tests. Currently pre-tests are mandatory and about 80% are taking them. At TUHH, pretests had been implemented as voluntary on-line supplements in the ET course for two years and in the GES course for one year. Averaged over the entire semester, student participation was relatively low in both courses: less than 40% in the English (GES) course and less than 20% in the German (ET) course. In the current academic year, different approaches were taken. In the ET course, pretests were no longer offered to the students. In the GES course, they were made an integral part of the course by awarding a small amount of credit (about 3% of the total credit points) for participation, regardless of the correctness of the students’ answers. As a result, average student participation in the on-line pretests rose to about 75%, which is comparable to pretest participation rates in Tutorial implementations at US universities. 3.2 Preparation of Tutorial instructors Due to the non-traditional teaching style that is being used in the Tutorials, any implementation of these materials requires a substantial amount of instructor training. In “standard” implementations at many US institutions (where the Tutorial sections are facilitated by undergraduate or graduate teaching assistants [TAs]), weekly preparation meetings are held for this purpose. During these meetings, first-time TAs are taking on the role of a student while more experienced TAs or other instructors may model the behavior of a Tutorial instructor. Ideally, seminars on student learning and results from physics education research complement these TA preparation meetings. At ITESM, some of the Tutorials are implemented during times that are scheduled as lectures, and are therefore facilitated by the lecture instructors. These instructors are full- or part-time employees of the university and are largely independent in their choice of teaching styles. There are three instructors’ meetings per semester, during which preparation for two Tutorials worksheets occurs each time. These meetings are conducted as described above, with the course coordinator acting as an experienced instructor. While it is not uncommon for instructors to miss some of these sessions, most of the instructors have attended at least one preparation meeting for each Tutorial that is currently being used in their course. At ITESM, undergraduate teaching assistants (uTAs) are hired to teach laboratory session and assist with instruction in lectures. Most uTAs are physics or engineering majors beyond their fifth semester with aboveaverage grades. All uTAs attend regular preparation meetings with the course coordinator. These meetings follow the model described above and occur in an environment that resembles the classroom where they will help instructors to implement the Tutorial. The remaining half of the Tutorials are implemented during laboratory sessions. Here, a single uTA serves as an instructor for 18 students. Undergraduate teaching assistants for the laboratory go through a similar preparation as those assisting the lecture instructors. At TUHH, Tutorials are implemented in small sections of less than 25 students in both the German (ET) and the English (GES) course. In the ET course, these sections are taught by one or two undergraduate teaching assistants (uTAs). As is the case at ITESM, the uTAs are physics or engineering students in their third or fourth year of studies. In most cases, they have not gone through Tutorial instruction themselves and are therefore required to attend a weekly preparation meeting similar to the ones described above. In the GES course, there is only one lecture section of about 25 students that is taught by one instructor. Tutorials are implemented in a workshop setting that is facilitated jointly by the instructor and an additional uTA. Largely due to the language requirement, uTAs for this section have always been students in the GES program and (apart from the first individual in this position) have therefore experienced Tutorial instruction in their own physics course. 4. ASSESSMENT OF MATERIALS AND DATA ANALYSIS Our assessment of the effectiveness of the materials and their implementation relies to a large extent on standardized multiple-choice (MC) tests. Such tests allow easy evaluation of large populations of students and comparison with results reported in the literature. However, to allow the instructor some insight into student thinking, the tests need to be constructed on the basis of prior research. If the distracters for each question form a complete taxonomy of alternate conceptions and learning difficulties, they can be used to obtain a picture of the students’ learning state, i.e. an inventory of alternate conceptions and their prevalence in a student population. When administered both as pre- and post-test, such questions can be used to study the progress of student learning and thereby assess the effectiveness of instruction in a particular course. Among the tests that fulfill these criteria, we chose the Force Concept Inventory (FCI) [5] and the Conceptual Survey of Electricity and Magnetism (CSEM) [6]. In some instances, we complemented these tests with free-response questions. Both the FCI and the CSEM contain questions from several concept areas or dimensions. The FCI is a 30-item test that is based on results of educational research about student alternative conceptions concerning force and motion. It is composed of six dimensions that are related to Newtonian mechanics: kinematics, Newton’s 1st, 2nd and 3rd law, the superposition principle, and types of forces. The CSEM is based on similar research on student understanding of electricity and magnetism. It is a 32-item test that covers 11 concept areas of electricity and magnetism ranging from Coulomb’s Law to Faraday’s Law with two to six items in each area. Since the CSEM does not include questions on electric circuits (which are part of the course content) a modified version of the CSEM (hereafter referred to as modCSEM) was administered. It consists of the entire CSEM plus 12 questions on electric circuits that were taken from the Electric Circuits Concept Evaluation [7] but modified to fit the format of the CSEM (i.e. five answer choices for each question). These questions on circuits add four concept areas: current, potential difference, equivalent resistance and RC circuits. For either test, a learning gain can be computed from pre- and post-instruction scores to assess the result of instruction. A formula for the relative gain [8] is given by Equation (1). g= χ post − χ pre 1 − χ pre (1) Here, χpost and χpre are the fraction of correct answers for an individual student or for the class average in the post-test and pre-test respectively. This parameter is widely used and is interpreted as a measure of what a student or group of students learned relative to what they could have learned. Gains can be calculated for a whole test or, if more detailed analysis is required, for a specific conceptual area of a test. 5. RESULTS At Hamburg University of Technology (TUHH), the assessment of Tutorial instruction has so far largely concentrated on administering the FCI. Pre- and post-test scores were used to calculate a relative learning gain. The resulting value (g = 0.50) in the course taught in English (GES course), is comparable to values found for research-based instruction at US institutions (g above 0.40). However, the outcome in the ET course using a translation of the Tutorials into German was substantially lower (g = 0.28). As mentioned above, the FCI is a standardized test that assesses students in six different areas or dimensions. Table 1 presents the relative learning gains corresponding to the entire FCI, its individual dimensions, and two specific questions, both for the course taught in English (GES) and the one in German (ET). Since the general gain for GES students is substantially higher than that of ET students, it is not surprising that in every dimension GES students have higher gains than ET students. However, the differences are not the same for all dimensions. The greatest difference is in superposition. GES students have a gain of 0.56 while ET students have a gain of only 0.08. Item/Course FCI Kinematics First Law Second Law Third Law Superposition Forces Question 4 Question 17 GES 0.50 0.34 0.56 0.38 0.53 0.56 0.48 0.91 0.68 ET 0.28 0.22 0.23 0.20 0.24 0.08 0.20 0.44 0.29 TABLE 1. Learning gain of GES students compared to ET students for the entire FCI test, the six dimensions and questions 4 and 17 of the test. In table 1 we also present results of questions 4 and 17 of the FCI to show examples of specific students’ conceptions and the differences on those conceptions between the two courses. Question 4 is related to Newton’s third law. The question asks students to compare the force that a large truck exerts on a compact car in a head-on collision to the force that the compact car exerts on the truck in the same collision. Students in the GES course perform somewhat better in the pre-test than students in the ET course. Only 22% of ET students chose the correct answer, i.e. that the forces are equal in magnitude. The remaining 78% of the ET students all chose the same incorrect answer, indicating that the larger car exerts a larger force. This answer is the most common misconception among college-level students, as reported in the literature. On the other hand, 35% of the GES students chose the correct answer. About 85% of the students answering incorrectly stated that the larger car exerts the larger force. After instruction there is a large difference in performance. While only 5% of the students in the GES course chose an incorrect answer, 54% of the ET students still answered incorrectly (with all of them choosing the most common misconception). It has been shown [9] that this alternative conception is very persistent also in other student populations. While the Tutorials seem to have helped most of the GES students to overcome the alternative misconception, they were not nearly as successful with the ET students. Question 17 is related to Newton’s second law. The question asks students to compare the magnitude of two opposite forces exerted on an object when it is moving at a constant velocity. The most common alternative conception is that for an object to be moving, a force has to be applied [10]. 20% of GES students chose the correct answer, i.e. that the forces are equal in magnitude in the pre-test. 75% of students with a wrong answer, chose an answer related to the most common misconception, the force in the direction of the motion has to be greater. The result of the post-test shows a very good improvement: 65% picked the correct answer. Among the ones choosing an incorrect answer, 71% chose the most common incorrect reasoning. On the other hand, ET students performed similar in the pre-test, 16% with the right answer and 74% of students with a wrong answer, thought that the force in the direction of the motion is greater. However, the post-test shows different results. About half of students were right and half were wrong. 74% of students who picked a wrong answer, chose the answer related to the most common misconception. The difference between GES and ET students in performance responding this question is not as significant as the previous, however, it shows that, in general, GES students (those who take the course in English) overcome students alternative conceptions better than ET students using the same instructional materials which are designed precisely with the objective of resolving students difficulties. At Tecnologico de Monterrey (ITESM), both the FCI and CSEM have been administered to students as a pretest before and posttest after instruction. Students taking physics at ITESM are divided into groups of 15 to 36 students. The groups are taught by individual instructors who are either faculty members or part-time lecturers. Although there are about 700 students each semester taking Mechanics and 500 students taking Electricity and Magnetism (E&M), results will be presented for only those students who are enrolled with instructors who use Tutorials. Figure 1 shows typical results of learning gain at ITESM for the CSEM in the Fall 2005 and Fall 2006 semesters as well as for the FCI in the Spring semester 2007. Learning gains are in general greater for the IP (those who take the course in English) students than for the RP (those who take the course in Spanish) students. The differences vary from semester to semester. A greater difference occurred in the Fall 2006 semester than in the Fall 2005 semester. In general the gains and the difference between the two groups are smaller in the FCI than in the CSEM as is evident from the figure. Figure 1. Results of different semesters of the CSEM and FCI at ITESM. The figure presents the learning gain of all students, IP (international program, in English) students, RP (regular program, in Spanish) students and some groups with instructors who taught at the same semester groups in English and groups in Spanish. In figure 1 some results of students from individual instructors are included. During the Fall 2005 semester, instructor B was teaching a group in the IP (in English) and another in the RP (in Spanish). The result for that instructor was that IP students performed slightly better than RP students. During the Fall 2006 semester, there were two instructors teaching E&M to groups in both programs. In both cases the difference between the IP students and RP students is significant. However, the FCI results of Spring 2007 semester show that 1) gains are significantly lower in the FCI than those in the CSEM for both programs, 2) IP students learning gains are greater but almost the same as those of RP students, and 3) for an instructor who taught mechanics in both programs, RP students performed better than IP students. A summary of results in the last four years at ITESM is presented in table 2. Summary of gains of FCI and CSEM combined in entire participant student population (8 semesters): • In four semesters IP-gain is substantially better than RP-gain • In two semesters IP-gain is slightly better than RP-gain • In two 2 semesters IP-gain is the same as RP-gain Summary of gains from instructors teaching both IP and RP groups (7 semesters): • • • • In three semesters IP-gain is substantially better than RP-gain In one semester IP-gain is slightly better than RP-gain In two semesters IP-gain is the same as RP-gain In one semester IP-gain is lower than RP-gain TABLE 2. This is the summary of learning gains for eight semesters. The left part shows the results for the entire populations of students both in the IP and RP. The right part shows the results for students in the IP and RP with instructors who taught the course in both programs. In general, there is a better performance of students in the IP program. In six out of eight semesters the learning gain of students taking the course (mechanics or electricity and magnetism) in English is greater than that of students taking the course in Spanish. In the other two semesters the gain is the same. Analyzing students of individual instructors who taught the course in both English and Spanish during a semester the result is similar. We presented results of the two institutions and found similar results. Students taking physics in English had better learning gains measured with the FCI and CSEM than students taking physics in the local language (German in TUHH and Spanish in ITESM). In the following section, we will discuss the possible reasons for these results. 6. DISCUSSION As indicated by the results from the FCI in both institutions and the CSEM at ITESM, students who are enrolled in courses in English performed better (in our study) than those in courses in the local language. There are several factors that may have contributed to this result. We believe that a large part of the observed variation is due to differences between individual instructors. It has been our experience in the past that a committed instructor with a well-chosen and clearly defined instructional strategy can have a considerable positive impact on student learning whereas a more traditional instructor is more likely to strengthen unwanted alternative conceptions in physics. We believe that this effect may account for some of the differences in student learning gains. To try to see how instructor affects learning gains, a report from uTAs (undergraduate teaching assistants who help instructors implement Tutorials in the classroom) at ITESM was introduced during the Spring semester 2007. In the report four items were assessed: 1) percentage of Tutorials implemented (how many of them were actually implemented), 2) percentage of worked Tutorials (an average of how far the students went working with Tutorials worksheets), 3) student work (an assessment of how students worked from a very collaborative way focus on the subject to a very individualistic approach or not focus at all), and 4) instructor interaction (the way the instructor implemented the Tutorial, from establishing a Socratic style instruction all the time to explaining/lecturing students all the time). With these four factors a grade was assigned to each instructor on a scale from 0 to 100 and a “level of implementation” between 1 (best) and 3 (least) was constructed. Results are presented in Table 3. Instructor Tutorials Extend Students (3) Instructor (3) Grade (100) Level 1 36% 40% 2 2.5 13 3 2 81% 45% 2 2.3 35 3 3 100% 67% 1.2 1.2 83 1 4 95% 93% 1 1 93 1 5 83% 68% 2 2.2 43 3 6 92% 66% 1.1 1.8 66 2 7 100% 92% 1.5 2.5 60 2 8 17% 80% 1 2 12 3 9 100% 89% 1 1.2 93 1 TABLE 3. Average results from the survey for the different instructors of E&M at ITESM. The grade is a factor that represents how well the implementation is done with that particular group of students who had that instructor. As Table 3 indicates, there are great differences among instructors. Implementation grades range from 12 to 93 (out of 100). The greatest influence to calculate the grade is the percentage of Tutorials implemented since the results of the other three factors is multiplied by this factor. This is done because no matter how well the instructor implements the Tutorial, if he or she implements two out of six, his or her students will not benefit at all from the other four. Instructor effect is related to implementation grade. The correlation factor between the average gain of students of each instructor and the implementation grade of each instructor is 0.81. This is a high correlation factor and means that instructors who are more committed to the instructional strategy had better results. An instructor who implements all six Tutorials, interacts socratically with students, guides them to work as far as possible with the worksheets and promotes collaborative work among the students, will obtain better results that instructors who do not follow this strategy. This is probably one of the most important factors of the difference in students’ learning gain. For instance, during the semester the report was implemented, instructor 4 was an instructor who continuously taught the English courses (International Program) and whose students have high learning gains. In both semesters Fall 2005 and Fall 2006, students of instructor 4 (course in English) performed better than the IP groups of instructors B and C in figure 1. However, there is still another factor since implementation does not explain everything. If we look at instructors B and C (instructors with a level of implementation of 2) in figure 1, we notice that even though the results of their students are above average in both programs (supporting the importance of instructor commitment), their IP students perform better than their RP students. There should be another factor. To see how important other factors are, a multi-variable analysis was performed. In the Fall semester 2007 we gathered information of students taking electricity and magnetism. We obtained their grade point average in high school (GPA), the TOEFL score at admission, the Lawson test [11] result (a test of scientific reasoning skills, from now on LAW), and the pre-test result of the CSEM (preCSEM). A simple correlation analysis of the CSEM gain against the mentioned variables shows that the Lawson test correlates most strongly (0.39), followed by the high school GPA (0.38), then TOEFL (0.27) and lastly preCSEM (0.17). Another interesting result is that TOEFL and Lawson correlate more strongly to each other (0.42) than any of them to the CSEM gain. These results indicate that statistically there is a relationship between the learning gain and the level of reasoning ability of the student and that the level of reasoning ability is related to the level of English proficiency. Therefore, the better results obtained by IP students compared to RP students at ITESM could be due to a better cognitive preparation of students since the level of scientific reasoning is better. A cluster analysis was done with results in the Fall semester 2007. The objective of that analysis was to find clusters of class groups that are statistically similar in their performance according to learning gain. With a level of similarity of 78%, it was found that there were five clusters given in table 4. Cluster 1 2 3 4 5 Groups 1, 2, 6, 7, 9 3, 5, 8, 10, 11, 12, 13, 16 4, 14 15 17,18 TABLE 4. Clusters of statistically similar sections measured by learning gain. Cluster 1 in table 4 is formed by groups with instructors with implementation level of 1 and 2. Cluster 2 is formed by groups with instructors with implementation level of 2 and 3. Cluster 3 is formed with groups with instructors with implementation level of 3. Cluster 4 is formed by one group, an instructor with implementation level of 1 who had only that group. Finally, cluster 5 is formed by two groups with the same instructor of implementation level of 1 who had only those two groups that semester. As can be seen, there is a very good relation between the level of implementation and how the clusters are formed. This result corroborates that instructor is an important factor for learning gain. 7. CONCLUSION In this paper, we have presented assessments instruments and data analysis for an investigation of student learning in an international context. The FCI and the modCSEM have been administered and results have been analyzed. Results from both institutions indicate that under the given circumstances students taking a course in English perform better than students taking a course in the local language. We have discussed possible causes and concluded that instructor qualification and commitment plays an important role, student reasoning skills as indicated by the Lawson test have a large influence, and students’ English proficiency is an important factor. These last two factors at ITESM are related to each other making difficult to generalize for other institutions. We are currently gathering more data in both institutions to better understand the phenomena. Also, we are analyzing the effect of the translation on student learning which it is possibly another important factor. Acknowledgements The authors acknowledge the support of the European Consortium of Innovative Universities (ECIU) project funds. One of the authors (GZ) acknowledges the additional support received from Tecnologico de Monterrey through grant number CAT050. References [1] L. C. McDermott and P. S. Shaffer, “Tutorials in Introductory Physics”, Prentice Hall, first edition (2002). [2] E. Redish and R. Steinberg, “Teaching Physics: Figuring Out What Works”. Physics Today 52, 24-30 (1999). [3] L. C. McDermott, P. S. Shaffer and M. D. Somers, “Research as a guide for teaching introductory mechanics: An illustration en the context of the Atwood's machine”. Am. J. of Phys. 62, 46-55 (1994). [4] L. C. McDermott and P. S. Shaffer, “Tutoriales en Física Introductoria”, Prentice Hall, pre-edición, Buenos Aires, (2001). [5] D. Hesteness, et al., “Force Concept Inventory”. Phys. Teach., 30, 141-58, (1992). [6] D. P. 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