The impact of an alternative approach to teaching in thermodynamics II using spreadsheets - a case study.
Since South Africa’s newly formed democratically elected Government in 1994 the face of South African education has changed across the board involving a paradigm shift from a content-based teacher-centred curriculum to outcomes based education (OBE), a learner-centred outcomes-based curriculum. This means that educators need to re-align their courses to that system and allocate appropriate resources to it. Hence the way one needs to go about educating learners has changed, and conversely, the learners themselves have had to face a change in learning tactics associated with the system. In light of the above, this study was undertaken to test an alternative method of teaching and learning. The subject chosen was a second semester introductory subject, Thermodynamics II, having several follow-on courses at higher levels. It is a subject that for many years has been considered internationally to be a “difficult” subject by many who have been through the system and one that in later life still tends to attract the same response. The study was conducted at the Durban Institute of Technology (DIT), formed from the merger of two former Technikons, Technikon Natal and ML Sultan, in 2002, now the Durban University of Technology (DUT), since 2007. The class was a fairly representative mix of race groups and gender. The study was a single case study, operating both within the positivist paradigm, the typical paradigm of scientific study, and the interpretivist paradigm, one in which students are often more involved in constructing meaning for themselves. The study was run over an eight week period, roughly the first term of a semester, covering the first few sections of the syllabus. The approach chosen was to halve the number of conventional chalk and talk lectures over that period, and using a constructivist approach to learning, to replace them by interactive computer laboratory sessions whereby students learnt the theory for themselves whilst at the same time using it to generate spreadsheet exercises to solve typical Thermodynamics problems. The idea was that students actually interacting with the basic requirements of the subject would hopefully develop a deeper level of understanding for the subject. The second term of the subject was handled in the typical manner of conventional lectures. There were three main interventions undertaken during the study period, namely two spreadsheet assignments undertaken using Excel, a student study habit survey and a concept test. Towards the end of the semester nine students from the class were interviewed. Each intervention is explained below. For the two spreadsheet assignments, a constructivist approach was taken with students working in groups of three to design the spreadsheets, the first to solve for the work done for any three consecutive processes forming a cycle, drawing the cycle on a pressure-volume graph. The second spreadsheet assignment was to be able to solve any problem associated with the non-flow energy equation and the steady flow energy equation, for any one unknown. At the end of each assignment each group had to peer assess one other group’s spreadsheet by using it to solve a problem. They then had to assess it guided by a rubric, considering criteria taken from the subject’s learning outcomes, writing down any good points and points for improvement. The study habit survey was a single page, two sided survey questionnaire, answered mostly using Lickert type scales and was handed out during one of the computer sessions. There were six main sections, namely personal information, information exchange, library use, subject specifics, practical experience/exposure and study techniques. A section was left at the end for students to fill any other information they wished to add. SPSS was used to analyse the information using cross tabs. The concept test was designed by the Researcher in Quattro Pro and was a multiple choice type questionnaire. It automatically marked the test by adding up the correct answers, giving the student immediate feedback at the end of the test by providing a percentage score for each of the four questions asked and a percentage score for the test as a whole. The test questions were based on the principles and methods that students would have used in the setting up of the computer spreadsheet exercises. The interviews were conducted individually for each student using a semi-structured approach. They were then transcribed and analysed using Transana. The information gathered from these, combined with information from the other interventions were triangulated where appropriate. Further, the two main intervention semester test scores were compared to each other using SPSS. Previous semester test scores were used as a control group and were also compared to the intervention semester test scores. Although the marks attained in the intervention semester did not show any major improvement when compared with other semesters, it did show that alternative methods of teaching and learning can be implemented within the mark norms. The study habits survey provided information about student preferences which will be helpful in future attempts at improving teaching and learning in this branch of engineering in this institution.