BLENDED LEARNING: SOME CASE STUDIES FROM CONTROL ENGINEERING

BLENDED LEARNING: SOME CASE STUDIES FROM CONTROL ENGINEERING

BLENDED LEARNING: SOME CASE STUDIES FROM CONTROL ENGINEERING J.A. Rossiter ∗ ∗ Department of Automatic Control and Systems Engineering, Mappin Street...

106KB Sizes 2 Downloads 45 Views

BLENDED LEARNING: SOME CASE STUDIES FROM CONTROL ENGINEERING J.A. Rossiter ∗ ∗

Department of Automatic Control and Systems Engineering, Mappin Street, University of Sheffield, S1 3JD, UK. email: j.a.rossiter @shef.ac.uk

Abstract: There are many pressures on university lecturers due in part to students’ not adopting proper learning styles. However, modern technology provides the lecturer with far more tools to create good learning environments which engage and assist the student learners (Laurillard, 2002). This paper presents some case studies of projects looking at the formal introduction of blended learning into the curriculum. The emphasise is on being imaginative, taking a few risks but also using technology only where it is most appropriate. Keywords: Interaction within a lecture, Web-based laboratories, quality assurance

1. INTRODUCTION It is well known that many students are motivated by deadlines and assessment rather than learning as an end in itself. It is also true, within the UK certainly, that students expectations and preuniversity training has changed substantially in recent years. It is essential that a lecturer understands this student outlook (Laurillard, 2002; Race, 2005), or they will teach in a manner that is not ‘fit for purpose’. For instance, in general students do not use learning resources because they are well designed or easy to learn from, they use them when forced to do so by impending examinations or courseworks (e.g. (Rossiter et al, 2005)). Where resources exist solely as ‘extras’, many students will not use them, no matter how effective they maybe in aiding learning. Increasingly academic staff, although appointed to do research, are being required to undertake formal training in teaching and learning so that they have a better understanding of how to facilitate learning and to understand different student learning styles (e.g. Kolb’s model is popular). However, despite this, the conventional didactic lecture still seems to be the most common method of delivery (Ramsden, 1992), perhaps nowadays supplemented with power point slides rather than the lecturer writing on the blackboard.

In the author’s department a decision was taken to take some risks and introduce some different forms of teaching by trying to make sensible use of new technology to enhance the students’ learning environment. Ultimately, the initial price of such change is academic staff time, however we intend to argue that in the longer term the staff member may actually save time as well as providing students with a better service. This paper will focus on two projects, both of which use technology in different ways. The first topic relates to MATLAB (Matlab, 2006). A fundamental aim is to introduce this software early in degree programmes for several purposes: (i) to empower students, that is, to give them skills that would enable them to use MATLAB for self-learning (self-testing) of other topics within their degree programme; (ii) to make assessment more sophisticated within the department and (iii) to provide an effective environment for illustrations throughout the programme. The hope is that by giving the students a large amount of material to get started and small but regular exposure thereafter, the main objectives would be met. This project is discussed in sections 2 and 3. The second project looks in more detail at the use of a virtual learning environment (VLE) (e.g. (WebCT, 2006)). The author’s department has a

policy that all modules should be supported by resources on the VLE, although for many this will just be copies of notes and tutorials. However, a VLE has far more potential for directing and facilitating student learning. Moreover, as will be discussed, it is a management tool that can greatly reduce both academic and administrative staff workloads as well as improving quality assurance. Section 4 will look at how a VLE was used to aid teaching of introductory control concepts. The paper finishes with some reflection, comments on evaluation and future directions.

2. LECTURE ENVIRONMENT FOR MATLAB This section looks at innovative ways of introducing and assessing matlab with engineering students 1 . We introduce and discuss the teaching context, aims and objectives and issues connected with the learning environment. We also discuss student evaluation of the learning experience.

2.1 The context in year 1 Within engineering, mathematics is primarily taught to support engineering and not as an end in itself. As a consequence, some effort is taken to ensure the students understand basic concepts, but there is less emphasise placed on cumbersome algebra (unless essential). Ordinarily, problems involving iteration or other computational demanding operations would be solved by computer. One can empower students by introducing them to suitable computational software early in their degree programmes. The hope is that, once competent in this software, they will use it to reinforce their learning and be more efficient in solving problems with lengthy algebra/computation. Typical topics might be matrix algebra, calculus, Bode and Nyquist plots, simulation of ODEs, modelling and simulation of time series, etc. As MATLAB is a well used and readily available package with large functionality, especially within control, this was chosen as the software tool. While it is accepted that MATLAB has numerous helpful demos, year 1 students are often not confident enough to self-learn with these and hence we introduce the software through more formal lectures and with formal assessment. Simulink is introduced in year 2 and not discussed here.

2.2 Module delivery: lectures or laboratories? To deal with lectures first, it is clear that where there are large student numbers, one may have no choice but to deliver content via a a traditional 1 Some of this work has been previously shown in a laboratory demonstration session in a UK based workshop sharing best practice (Rossiter, 2005).

didactic fashion within a lecture theatre. However, our experience is that although this allows high quality demonstrations and staff to respond dynamically and visually to student requests, it also has all the well known weaknesses of lecturing, but amplified. To encourage deep learning (Ramsden, 1992; Fox, 1983) students need to be actively engaged rather than passive observers. This obviously implies not only engagement with the relevance of the subject matter but moreover good lecturing practise advises that student concentration and learning is better when there is frequent student activity within the lecture as well as changes in activity every 10-15 minutes. As this module was based on MATLAB, any activity would logically involve the construction and testing of code and thus students need to be sat at a computer during the class. Consequently, as our numbers are usually below 80, the department decided to move lectures into a computing laboratory as this enables the students to be fully active during the lecture. In theory, a computer laboratory is an ideal environment as the students can learn by doing which improves understanding and memory. However, most computer laboratories are not designed for lecturing so there is the counter disadvantage that one may not be able to lecture. A typical difficulty, encountered by the author, is caused by computer laboratories having low ceilings; this means that overhead projection is not viable.

2.3 Using the web to enable interaction with a laboratory based lecture This section considers two practical aspects of teaching within a laboratory: (i) how do you present information without overhead facilities and (ii) how do you facilitate interaction with the students? In particular we discuss how technology can be used to overcome these limitations and, even more importantly, we show how this can be done with ‘cheap’ and hence readily available software. The context is very specifically linked to MATLAB although the general message of be imaginative carries across more widely. This section focuses on the need for the lecturer to: (i) illustrate code (teaching); (ii) create new code during the lecture to respond to student enquiries (interaction) and (iii) moreover, to facilitate student engagement (deep learning). To achieve the above, the lecturer needs a facility to pass ‘new’ code to students instantaneously, and without conversion errors, during the lectures. 2.3.1. Ready prepared files on a common access server In the absence of an overhead facility, one can, to some extent, still present examples to the students by careful preparation. Specifically, one can create code, such as the built in demos, to illustrate concepts. Most universites have shared servers to which students have read

access. MATLAB allows the user to set a search path (via an addpath statement) and will look for files on that path. In the author’s department, they create separate folders, and hence addpath statements, for each module. These folders may contain exemplars and useful files in support of a module. Most significantly, it is an easy way to pass complete files to students. In addition, the lecturer can edit the source quickly and the change is then automatically made for all students. 2.3.2. A dynamic webpage linked to a lecturer controlled source In general, a lecture context will be focussing on small blocks of code rather than whole programmes. Moreover, the desire for rapid interaction with and between students means that there is a limit to the usefulness of shared server files. For instance, in response to a query, there may be a desire to send students a small block of code illustrating a given operation. Ideally, the lecturer would be able to write and send to the students a block of code to try. Students should be able to execute this code by cut and paste or some other rapid and low-error process. We found the most efficient way to do this was via a webpage linked to a editable source. The students open the relevant webpage, which is pointing at a source on the shared folder and refresh as required. The lecturer edits the source during the lecture (we do this using Microsoft word and then save as html). The lecturer can cut and paste direct into the web page from MATLAB and the students can then cut and and paste from the webpage back into MATLAB so the whole interaction can be handled in a few seconds, with no transmission errors. To facilitate this, one needs a networked source to which the lecturer has editing rights from within the computer laboratory. Our experience is that this was very effective, and required students to have open only a single webpage in addition to MATLAB. The only downside was that it was one way communication. Most significantly however, it allows the lecturer to send the students an arbitrary number of lines as appropriate, and also to control the lecture by sending only the lines required at the time. It is also easy to add comments in between the lines of code (to appear on the webpage) to aid clarity. 2.3.3. VLE based tools Many Universities have adopted VLEs and these contain many tools that facilitate different teaching styles, although in this case we found them of only small benefit during lectures themselves. Specifically we investigated two tools before the approach in the previous subsection was available. The first was to use a chat room to facilitate interaction between students and staff. Students log into a chat window during the lecture and can pass (via cut and paste) commands and comments to each other. This is excellent for enabling student to student interaction during a lecture and allows the lecturer to send commands instantaneously,

and accurately. However, the chat window available to us only allowed one line to be sent at a time which was very inefficient when discussing chunks of code. Moreover, students often abuse the facility in lectures causing the chat window to be flooded with spurious messages. If the laboratory set up allows it, then an interactive whiteboard which displays on all the student screens, is also an ideal means of replacing the interaction usually performed on an OHP. A VLE may contain a form of whiteboard, however in the case of WebCT it was not possible to do freehand sketching on this as operation was solely via a mouse; consequently that tool was too clumsy to use to be effective. 2.3.4. Faciltating learning in the lecture It is the author’s belief that students learn to programme and use software only by doing it themselves. MATLAB however is more than just a programme and there is a need for the students to have an inquisitive nature, thus asking questions: ”if that command did this, what would happen if I changed it to ** ?” This belief underlies the lecture style adopted. Being honest, most students find this works well for them, but there is still a significant minority who cannot deal with the independent thought being asked of them and want a much more prescriptive or spoon feeding style; the latter students, not always the least able, struggle more with the course. Hence, the lecturer gives students a few lines of code and asks them to decide what the code does, often just be implementing it in MATLAB. Next, they are asked to modify the code to test if their interpretation is correct. Clearly this procedure can build to fairly advanced algorithms. It is accepted that progress is slower with this approach, but the learning should be deep rather than surface (Ramsden, 1992) thus empowering students to self-learn more advanced topics later. 3. ENSURING STUDENT ENGAGEMENT AND EVALUATION Students engage most when they are clear how a skill will be assessed, and more so when a lecturer enthuses them by making the topic relevant and interesting 2 . Hence, in the introductory module to MATLAB, we: (1) use frequent but transparent assessment of key skills to ensure active participation. (2) build the assignments around problems of obvious relevance to engineers (but accessible to year 1 students). (3) include some open-ended assignments to allow students to be imaginative and have fun. (4) build in either instantaneous feedback if possible or alternatively fast formative feedback. 2 (Race, 2005) Model of learning - a want/need to learn, doing something to learn (an activity), digestion, feedback, assessment.

The main aim is that the students become confident in the use and potential of MATLAB and thus in a state of mind that quickly thinks of using this tool later in their studies.

3.1 Assessment Assessment must be matched to the learning outcomes. In this case these are to become proficient in MATLAB and aware of its potential. It was felt that such aims were best met by regular assessments, each with detailed formative feedback, thus encouraging students to progress steadily. Hence the module is based around 3 courseworks, which require gradually more advanced skills and are designed to help scaffold their learning (Oliver et al, 2003; Roblyer et al, 2000). • The first coursework tests elementary uses of MATLAB, but is given early in the semester as an incentive for early engagement. It involves simple mathematical operations with matrices, vectors, complex numbers, function evaluation and numerous plot types. • The second coursework uses problem based learning (PBL) to emphasise the effectiveness of MATLAB with engineering problems. It introduces formal programming as a by-product. Students investigate simulation, time series, numerical methods, discretisation, optimization, etc.. This is a group project to encourage peer learning (i.e. we understand best when we teach). • The third coursework is more for fun but is to encourage students both to exploit the built in functionality of MATLAB and to further motivate them by showing the ease with which an advanced GUI can be constructed to aid their learning of ODEs, damping etc..

3.2 Enabling rapid formative feedback for large groups Regular and fast formative feedback is essential to student development (Brown, 2006) . This was a major reason for having the first assignment after just 4 weeks as it gave the lecturer an opportunity to engage with the students and discuss one-toone their progress. Nevertheless, it is clear that the time required to give detailed feedback on the code of a whole cohort is simply prohibitive and thus it was necessary to find mechanisms that allowed the students rapid feedback on their code. Again, the idea is to be imaginative with the resources available. Here the author designed automatic marking code. (1) Precise instructions for all filenames in the submission enables automatic operation of all submissions given the userid. (2) Earlier courseworks very prescriptive in the numerical operations required, but based on randomly generated data, thus no two students ever received the same data.

(3) Lecturer creates code (on the common server) to generate correct numerical answers and this code runs students’ file and then compares their output with the correct output. (4) Students execute the lecturer’s code to selftest before submission. Code reports precise points where they give correct and incorrect numerical answers and also gives pointers on the non-numerical marks available. In fact, although the automatic marking code is cumbersome to write, it does not take long and can be made robust with try-catch loops. It enables students to self-test (instantaneous feedback) and this gives them an added incentive to keep working until their submission is perfect. As a consequence, the one-to-one marking can focus on issues such as code structure, commenting and errors. This is always timetabled within a week of submission to ensure the feedback occurs while the issues are still fresh. Generic feedback on common errors is posted to all students. On going formative feedback is also enabled by regular laboratory sessions with several demonstrators. 3.3 Evaluation and student response to the module Despite the difficulties encountered in having a non-ideal laboratory environment, that is one lacking good OHP facilities (students did comment on this) with which to do free hand illustrations, students were very positive about the usefulness of this module. A few typical comments are given below: ”Matlab - easy if you use logical steps and the reference material available. Enjoyable module”, ”I think it was a good idea to use computer lab to teach about Matlab instead of lectures. It is more practical and interesting”, ”An interesting and useful module, with good coverage of some of Matlab’s features”, ”Found it quite difficult at first, but then realised I have to work on my own to really master Matlab.” In summary: students like being taught software related topics in a laboratory so that they can try things out as you introduce them. There are many software tools available to create an interactive environment for teaching. We found a shared server facility and a dynamically editable web-link to be very useful for passing chunks of code to students. We also found that automated marking encourages participation and student learning. 4. MAKING USE OF A VLE TO ENHANCE THE LEARNING ENVIRONMENT The next project is focussed on a more conventional topic, frequency response methods for control engineering. Specifically this covers what is a frequency response, Bode diagrams, Nyquist diagrams, gain and phase margins and an introduction to lead and lag design. Once again, the purpose of this paper is to demonstrate how modern technology can be used imaginatively to enhance

the student learning experience and at the same time give benefits to the lecturer/department.

increasing problem within the UK and is a major reason for using exam only assessment.

First we give some generic background on the use of VLEs and then focus on the specific project. Special focus is given to avoiding plagiarism and improving student engagement.

Exam only assessment is not always appropriate and also mitigates against the need for encouraging regular working and formative feedback through regular assignments. Typically, VLEs include a quiz environment which allows the lecturer to automate setting every student a slightly different assessment through a random number generator (or otherwise) and hence to make it much harder to copy or collude. This facility is widely used in the mathematics community (Mathcentre, 2006) and medicine, but less so in other fields.

4.1 Background to using VLEs for assessment Typically a VLE might be thought of as a distance learning tool, or as part of a blended learning package including lectures with the VLE giving other resources. Our experience (which is relatively well known) has been that simply putting resources on a VLE is an ineffective use of staff time (Rossiter et al, 2005). Even excellent resources are not used by the majority of students if assessment does not appear to be directly related. The challenge is to integrate different learning resources in a way that enhances the learning environment but also requires the student to engage. Sadly, the main tool seems to be assessment (Race, 2005), but this is where a VLE really helps. One of the disadvantages of regular assessment is the potential workload implications (extra marking for academic staff and extra administration for the secretariat). Moreover, quality assurance requires two conflicting demands: • Students should receive detailed feedback on all submitted work within 1-2 working weeks. • The department should retain all submitted work for review by the external examiner. With handwritten assessments, this could imply the need to take copies of all student work, or to place feedback on a separate sheet, thus making it less effective. There is also a storage issue. Moreover, this amount of marking is untenable in general for large classes. Use of the VLE tackles two of these issues. • Submissions via a VLE are automatically date stamped and have a personalised feedback box. This avoids need for receipts or to submit at set hours to an office. Also the assignment is in a form that can be submitted to plagiarism detection software. • The courseworks are all stored on the VLE and hence can be viewed, with feedback by external examiners. This also removes the paper storage requirement. The last issue of marking load requires some thought about the form of assessment, but this also links into quality assurance discussed next.

4.2 Using computer aided assessment to reduce collusion and plagiarism When formative feedback is important, then the assessment must be designed to facilitate rapid marking. Unfortunately, such assignments may be easier to plagiarise and as student cheating is an

Quizzes take substantial time to create but thereafter have a reasonably long shelf life and can be embedded in a module with relatively small ongoing time input. Most importantly, these can include formative feedback on questions students get wrong. Moreover, as an incentive to learn more, many departments use the paradigm of allowing students unlimited access to selfassessment quizzes for preparation before releasing the actual assignment. Many students take this as a challenge and prepare so well that 100% is not unusual (Rossiter et al, 2005; Mathcentre, 2006). The project discussed next makes use of CAA for frequency response methods and in particular to improve the efficacy of laboratories.

4.3 Improving learning of frequency response methods through a VLE A basic tool within control is frequency response methods such as Bode and Nyquist plots. Many UK students struggle to grasp this because of a lack of fluency with complex algebra. Using the usual didactic lectures and final exam often does not engage the students in a topic that, to them, appears rather abstract and confusing. Even though MATLAB based examples may be spread throughout lectures and notes to help insight and learning, the majority of students do not use these resources, predominantly we assume, as there is no direct credit for doing so. Our solution to this involved two changes. First the existing laboratory was redesigned to integrate and bring to life their understanding of frequency response methods by introducing a session solely on MATLAB to help focus on key concepts. However, again, students made very slow progress, many hardly getting past the introductory questions asking for simple computations of gain and phase. It was deduced from student comments that they simply had not prepared; adequate preparation is essential for a laboratory to be useful. This left the dichotomy, do we assess student preparation given this is time consuming if done properly, but, on the positive side, would also be an opportunity to give formative feedback?

4.3.1. Ensuring students prepare for laboratories Ironically, ensuring students prepare properly comes back to the earlier message; students work more when they get marks for doing so. There was a need to give credit for proper preparation, but without substantially increasing staff workload. As hinted at above, the CAA environment is a natural means of handling this. Hence, the decision was taken to move the laboratory preparation to CAA on a VLE. This had several advantages: (i) Students could repeat the preparation as many times as necessary to achieve the required mark. The questions can be varied each time so that simply copying would not improve a student’s mark; (ii) students get instantaneous feedback on their preparation, 24/7! (iii) The preparation quiz can be embellished to also encourage students to engage with and learn basic knowledge and (iv) the VLE can be set up to automatically hide the laboratory session until the student passes the preparation. Without adequate preparation, the student cannot do the laboratory. Although a few students found this hard, most just accepted it and worked hard on the preparation to optimise their mark and to ensure they could attend (and thus get the marks for) their laboratory session. Remark 4.1. An interesting observation is that the students only seem to be doing the preparation quiz because they get credit for doing so. In class comments and student feedback suggest that the majority are not selecting the neighbouring icons on the website giving other useful information about the laboratory and thus still turn up less prepared than they could. 4.3.2. Quality assurance issues As part of this project, we also asked the question whether a VLE could be used to help with the administration (Quality assurance, collusion, etc.) of the laboratory session. As a trial (now in its second year), the laboratory sheets were available only via the VLE and not as hard copy (although typical questions could be printed off anytime). During the laboratory session, the students enter their responses and figures, on line, direct onto the VLE. In our experience advantages are that: • this ensures the department, the student and the external examiner can view their responses and demonstrator marks/comments. • the laboratory session is formally managed without the need for careful invigilation: (i) availability linked to preparation; (ii) strict start and end times can be set on the VLE and (iii) reduces collusion during (or before) the session as students all get different questions. Face-to-face marking is still straightforward with the only difference that the demonstrator enters comments and marks direct onto the VLE while talking to the student.

5. CONCLUSIONS This paper has presented two case studies of using blended learning to enhance student engagement, and thus learning. It has been shown that modern technology can be used imaginatively to the benefit of students, academic staff and administrators. Significantly, at a small cost to set up times, academics can generate assignments that give students instantaneous formative feedback and thus encourage active participation and growth. Using a VLE or other random question generator can also ensure that each student gets different questions and thus reduce collusion. In terms of the future, many of the topics in years 1 and 2 are very similar across the globe and I would like to see a proper mechanism for sharing resources such as CAA to reduce the onerous parts of the task, such as the initial set up. Acknowledgements: Thanks to Dr D. Rossiter for proof reading and comments on this article.

REFERENCES Brown, S., Using formative assessment to promote student learning, University of Leeds Learning and Teaching conference, 2006, Keynote Carpenter, S. and Simons, S (Eds), Engineering subject centre: Guide to lecturing, The HEA engineering subject centre. Coffield, 2004, Learning styles and pedagogy in post 16 learning: A systematic and critical review, www.lsda.org.uk/files/PDF/1543.pdf Fox, D., Personal theories of teaching, in Studies in Higher education, 1983, 8(2), 151-163 Laurillard, D., Rethinking University teaching, Routledge, 2002 Mathcentre (Loughborough, UK), www.mathcentre.ac.uk, www.lboro.ac.uk/research/helm/index.html MATLAB, http://www.mathworks.com Oliver, R. and J. Herrington, Exploring technology mediated learning from a pedagogical perspective, 2003, Journal of interactive learning environments, 11,2, 111-126. Race, P, 2005, Making Learning Happen: A Guide for Post-Compulsory Education’, publisher: Sage (Paul Chapman Publications), Ramsden, P, Learning to teach in higher education, 1992, London, Routledge Rossiter,J.A., L. Gray and D. Rossiter, Case studies of the resources students use, IFAC world congress, 2005 Rossiter, J.A., Experiences of supporting mathematics learning through MATLAB and a VLE, Helping everyone learn Mathematics, Loughborough, Sept. 2005 Rossiter, J.A., D. Rossiter, Student usage of web-based resources for engineering teaching, UKACC 04 Roblyer, M.D. and J. Edwards, Integrating educational technology into teaching, 2000, Saddlebrook, Prentice Hall. WebCt, http://www.webct.com