Department of Physics and Astronomy, University of Leicester
Wednesday 16th January 2002
Problem-based learning (PBL) is becoming increasingly popular across a wide range of disciplines. In the phyical sciences it is still relatively new and there is much debate as to its usefulness and applicability. The aim of the workshop was to discuss the definitions of problem-based learning and explore its possible uses in chemistry. The workshop (attended by 37 participants from 26 institutions) had a common morning with 'Problem Solving in Physics and Astronomy' workshop (attended by 22 participants from 19 institutions). This was followed by four presentations on the uses of PBL in chemistry. The workshops were sponsored by the Royal Society of Chemistry and the Institute of Physics.
Professor Lewis Elton, University College London.
Contact: l.elton@ucl.ac.uk
Problem Based Learning (PBL) has not been evaluated to any great extent outside medicine. Lewis considered whether there were differences between disciplines and, with input from the audience, concluded that there are differences. The learning objectives of PBL included key skills, independent learning, problem solving, communication, discipline specific skills and a multi-disciplinary approach.
PBL turns the curriculum back to front. The students start with the problem which leads them back to the theory. It allows knowledge to be linked to applications, better skills development and greater motivation of students. The main disadvantage is that it point to unsystematic knowledge acquisition.
In Medicine the overriding skills objective is the development of diagnostic skills. The problems arise from real or pseudo real situations. The three types of problems used in the teaching of medicine are computerised simulations (experiments), design problems (use of actors showing symptoms to be diagnosed) and finally real patients. Engineering has a more systematic knowledge base than medicine. In pure disciplines (e.g. physics, chemistry), with its systematic knowledge base, the problems are generally used to illustrate this.
In the Feynman Lectures on Physics (1963), the rubric for the first set of exercises read: 'Use the ideas outlined in this chapter, together with your own experience and imagination, in analysing the following exercises. Precise numerical results are NOT expected.' Lewis Elton said, "this is the germ of PBL and Feynman rejected Kelvin's view that 'if you cannot measure it then it is not worth having.'"
The purpose of teaching is learning. Students should learn to think constructively, to argue coherently, to judge dispassionately and to tackle problems effectively. This is often at variance to university education. Students should be encouraged to learn actively and with commitment, formulate their own learning objectives, use their past and current experiences, and think critically. This is where PBL comes in.
Humbolt (1810) stated, "Learning should be not in terms if receiving well-established knowledge but of not yet completely solved problems." The traditional lecture is scholarly for the teacher but not the students, for whom it is transmitted knowledge received passively. Teaching must be at the sophistication level of the students and involve them actively. Students at a higher level see too much in simple problems.
According to Boyer, there are four kinds of scholarship.
Traditional universities only recognise the first. However, teaching should encompass all of these so is similar to research. PBL teachers are research orientated, not necessarily researchers. PBL requires the scholarship of teaching, practice and integration but only rarely that of discovery.
The real problem for PBL and other modern appreaches to teaching is the changing of attitudes. Teachers need to change from discipline based to problem based curricula, from teaching to facilitating learning and from teacher sophistication to student sophistication (in other words put the students first and remember to talk at their level rather than your own). Heidegger stated, "The teacher is ahead of his apprentices in this alone, that he has far more to learn than they - he has to learn to let them learn."
Students need to move from passive to active learning and from dependence to independence. Students learn well from other students so they can learn to challenge ideas because we are in awe of our teachers. This should not be considered as the blind leading the blind.
The myth that 'Research benefits teaching per se" is possibly true for the top 10% of students because they do not need to be taught. The other 90% must also have the right to learn.
And yet the charismatic teacher can convey the love of their subject to their students so that while they do not teach them, they motivate them to learn. This was certainly the justification for this excellent lecture about aspects of Problem Based Learning.
Question: Can you mix PBL and traditional teaching methods?
Answer: The orthodox view is that you cannot mix as this would confuse the
students. However, in one medical school PBL was introduced progressively.
Question: How do you select the problems?
Answer: The selection of problems depends on the extent that a discipline has a
general underpinning of theory. Problems are never single discipline.
Question: What about assessment?
Answer: It must be related to group work with some scope for individual
differences, whereas, traditional assessment is based upon independent
assessment of individuals.
Question: When should we start with PBL?
Answer: Students should be introduced to PBL at the beginning of their course
in the first three weeks of the first term before the pattern is set in the
student's mind.
Question: What would you say about group work?
Answer: We ought to provide a place for group work. Some students are unhappy
with group work and they should not be forced. Although they may be persuaded.
Dr. Alan Heaton, Liverpool John Moores University
Contact: c.a.heaton@livjm.ac.uk
Alan began by questioning exactly what we mean by "problem". He referred the participants to Alex Johnstone's categorisation of problems by factors such as whether all data is given, whether the methodology is given and whether the goal is clear.
| Problem Type | Data | Methods | Outcome/ Goals |
|---|---|---|---|
| 1 | Given | Familiar | Given |
| 2 | Given | Unfamiliar | Given |
| 3 | Incomplete | Familiar | Given |
| 4 | Incomplete | Unfamiliar | Given |
| 5 | Given | Familiar | Open |
| 6 | Given | Unfamiliar | Open |
| 7 | Incomplete | Familiar | Open |
| 8 | Incomplete | Unfamiliar | Open |
Alan pointed out that the majority of problem solving for undergraduates is merely solving exercises, which gives no experience of "what we do when we don't know what to do". Most problems set currently fall into types 1 and 2. A number of examples were used from Crawford and Heaton (1998), Problem Solving in Analytical Chemistry, where the participants were able to try out some of Alan's problems that were either open ended in nature or required the use of unfamiliar methodology. Copies of Alan's book can be obtained from the RSC.
References
Dr. Stephen Summerfield, University of Hull
Contact: s.summerfield@hull.ac.uk
The aim of the project was to develop a series of problem solving based case studies on areas of analytical chemistry that focus on industrial, environmental and forensic topics. The case studies are based upon real events or problem based scenarios. They are designed to provide a context within which students can tackle problems and make decisions. The case studies involve the learning of chemistry by building on and showing the relevance of prior learning, are interactive in style set within a work-related context and involve personal skills development. Each case study will be set within a fictitious county called Midshire. In addition, the case studies are designed to be modular allowing the flexibility of the lecturer to choose those elements that are relevant to the course and students.
The Chemical Detective (The Pale Horse)
This level 2/3 forensic analytical case study is set within an
investigation of a (fictitious) suspicious death. The aim is to provide
students with a 'real' context within which to extend their knowledge of
analytical science. The evidence is presented in reports from the attending
police officers, the investigating officer, the forensic medical examiner, the
scene of crimes officer (SOCO) and the forensic scientist. From these, the
students decide upon what to analyse and the methods they wish to use. Results
are given to them when a suitable request has been made. From these and other
evidence, the students are able to identify the cause of death, and method of
application.
Who Killed the Fish?
This level 2/3 environmental river pollution problem-based case study is
set within the fictitious Coley River system. Students investigate pollution
incident(s) that have impacted upon the environment of a river, initially shown
by changes in the fish population. The environmental problems encountered are
organic, inorganic and physical in nature. The concept behind this multifaceted
case study is to produce a problem that appears simple initially becoming more
and more complex as the investigation proceeds. The scene is set in the first
session with a letter from anglers who have complained about observing a
reduction in their catch.
The Titan Project
This level 1 industrial analytical case study (based upon 'The Titanium
Dioxide Group Exercise' by Dr. Tina Overton) consists of two main sections that
could be run together or separately. The first part of this case study uses a
comparison of both processes for the industrial production of titanium dioxide
as a vehicle to encourage students to consider industrial chemistry in a broad
context and the corresponding safety, environmental, economic and social
issues. In the second part the students consider setting up an Environmental
Monitoring Laboratory for the chloride process. They must select and evaluate a
new method of analysis for chloride ions in river water. The students survey
the analytical methods of analysis for chloride ions in water. The pros and
cons of the various methods and statistical evaluation of each are carried out.
All the case studies presented have been very successfully trialled at least three times with different students at a number of institutions. A number of other case studies are under development to cover other specific areas of applied and analytical chemistry. Copies of the case studies may be obtained from either Dr. Stephen Summerfield or Dr. Tina Overton.
Dr. David McGarvey, Keele University.
Contact: d.j.mcgarvey@chem.keele.ac.uk
David has produced a number of phyical chemistry practical problems that use a a 'real' context and they provide no detailed instruction but expect the students to work in groups in order to plan and carry out an investigation. The context of the experiments were Level 1 (a familiar yet spectacular phenomenon of chemi-luminescence from commercial lightstticks) and Level 2 (solubility and kinetic salt effects) Core Physical Chemistry. The key aspects were team work (3-5 students), deciding what data is needed, formulating an experimental approach, planning an experimental method, drawing on a breadth of knowledge and critical reflection. The rationale was to let the students work it out for themselves. The students had to draw upon a wide breadth of knowledge, develop skills and reflect critically. David concluded that it had been very successful although next time more time would be set aside for the students to plan the experiments.
Dr. Angus McDougall, UMIST.
Contact:
angus.mcdougall@fs1.ch.umist.ac.uk
Angus outlined the collaboration of the Chemistry and Physics Departments at UMIST and Manchester University to address the problems of the transition from secondary to tertiary education that was in its early stages. The project is looking at how prepared the students are for practicals by use of a two-page questionnaire administered by independent parties. It was not anonymous because of the requirement of subsequent follow-up. Context-based laboratory work will be developed, implemented then contrasted with traditional practical work. Students on both traditional and context based modules will be surveyed.
Report by...
Dr Stephen Summerfield
University of Hull