In Chemical Engineering, the general approach is to prepare students for careers in i) design ii) process engineering and iii) R & D. In order to be competent, modern day chemical engineers, students need to have i) a good grasp of the fundamental physico-chemical principles and ii) the ability to see the links among them. Mathematics comes into play when these principles are applied to process design. Generally, students do well when it comes to applying the principles to standard, repetitive situations. However, students lack the ability to link and apply the principles to non-textbook (novel) problems.

The above scenario is analogous to teaching basic mathematical operations to school children first and then asking them to solve math word problems. Most children will do very well in questions dealing with basic symbolic operations (category I questions). The children will also be comfortable if the word problems appear at the end of each chapter on a symbolic operation, because they will know which operation is involved (category II questions). The true test of understanding begins when the children are given exercises on word problems taken from different chapters (category III questions). The ultimate challenge for the children would be to ask them to solve word problems that involve the use of multiple dissimilar operations (category IV questions).

At the end of the day, in most of the process-based engineering modules, students should be able to apply the principles covered in the respective modules. In general, the tutorial problems fall under category I questions, quizzes can be classified as category II questions and the exam questions are category III questions (at best). We hardly challenge students with category IV questions to avoid causing a potential disaster.

An example of a question I had set in a postgraduate examination paper is given in Figure 1. A good answer to the question should address the following issues:

i) What is the controlling resistance?

ii) If the controlling resistance is on liquid side and the patented solution introduces reaction with absorbed carbon dioxide, then it is possible that the column height will be reduced.

iii) The claim that the patented solution will give the smallest column height needs fur ther investigation.

 
Figure 1. An example of a question from a postgraduate examination paper (Semester I, Academic Year 2002/2003).

Less than ten students (out of 116) came close a good answer. The students would have been very comfortable if I had asked:

i) What is the controlling resistance?

ii) What can you do to reduce the resistance on the liquid side?

One common criticism encountered in NUS is that there is a general tendency among lecturers to overload students with information. Thus, they are left with no time (and space) to learn independently and think critically. Undeniably, space creation is necessary if we want to encourage independent and critical thinking in our students. However, does space creation mean a mere reduction in students' workload in good faith that independent learning and critical thinking will follow spontaneously?

Let us examine an example. Recently, the Department's third-year laboratory module (CN3108 "Chemical Engineering Process Lab II") was reorganised following the practices in similar laboratory module in two top US chemical engineering departments. Students now spend two days on each experiment instead of one day per experiment prior to the reorganisation. It was expected that students will utilise the extra time to do more critical thinking and independent learning. In reality, did the extra time given bring about any noticeable qualitative changes in students? Based on my personal experience, the answer is not an enthusiastic 'yes'. I had to spend over one hour with each group to ask questions and (through these questions) guide students on how they could make use of the extra time to improve the experiment and apply the relevant theories covered in lectures to analyse the results meaningfully. The less serious students were, of course, lost. But those who learned the relevant module well could recall the theories I referred to. What students (including top students) could not do was to make the 'connection' on their own. I call this the first step in independent thinking and critical learning. This is just one example, but I think it is a good one to take my point seriously.

We often tend to forget that students have undergone 12 years of schooling, which left a profound influence on how students approach learning and perceive education, before coming to the university. It must not be overlooked that university cannot undo twelve years of grooming in an examination-oriented environment where the ownership of learning was never with the students. When Prime Minister Lee in his first National Day Rally speech said, "We've got to teach less to our students so that they will learn more"¹, he did not say that with reference to the university education; he said that about the education in schools and junior colleges. I thought that was a profound statement and a move in the right direction. Prime Minister Lee recognised that teaching less must go hand in hand with creating an environment where the created space is filled with alternative activities that promote independent learning and critical thinking. He also recognised that sustaining such an environment can be demanding on teachers and that is why he promised to increase the number of teaching positions for the schools and junior colleges in the coming years.

I am not in any way trying to say that NUS should wait until the new waves generated at the schools reach the university. My point is that independent learning critical thinking cannot be forced upon students-it should be a spontaneous part of their upbringing and their everyday environment. Without such induction, any extra space created will be wasted by the majority.

Hence, any move to reduce classroom teaching or other tangible workloads to create meaningful learning space for students must be supplemented by alternative strategies to ensure an environment conducive to independent learning. We must then dispel the notion of equating reduced classroom teaching to a reduction in teaching load. In fact, developing innovative ways and means of promoting independent learning and critical thinking are much more time consuming than the demands of conventional pedagogy. In addition, large classes can further increase the demand for time and resources necessary to implement even tested pedagogical strategies to promote independent learning and critical thinking. Therefore, we must address these issues adequately before launching the next round of content reduction.

¹ Prime Minister Lee Hsien Loong's National Day Rally 2004 Speech, "Our Future of Opportunity and Promise". Delivered on Sunday, 22 August 2004, at the University Cultural Centre, National University of Singapore. (Last accessed: 22 August 2006).

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