In 1923, the respected biochemist and philosopher of science
Haldane stated, “It is the whole business of
the university teacher to induce people to think1”
The laboratory class is a marvellous medium to encourage this
and to help students construct knowledge. The environment
is intrinsically student-centred: the student performs the
experiments and interprets the results. On occasion, students
need to work in small groups, either because of the complexity
of the experiment or the availability of the equipment. In
so doing, laboratory classes promote peer learning, teamwork
and interpersonal skills. In addition, many of the experiments
are problem-based in design which should help students understand concepts and theories2.
However, perhaps the strongest motivating factor in favour
of the laboratory class as a learning environment is the fact
that students get to create things; and quite frankly, creating
things is fun.
It is perplexing, therefore, to witness the laboratory class
failing to realise its potential. This issue is pretty much
universal in higher education. In Britain, Byers recently
commented, “All too often students see laboratory work
as a form of assessment rather than as an
opportunity to learn3.”
I believe that the problem is indeed an issue of motivation.
However, the issue of motivating students is not unique to
the laboratory setting. Thus rather than focussing on the
laboratory, I wish to use the example of the laboratory class
as a device to discuss the wider issue of inducing students
We need to first consider what we want students to learn.
de Bono wrote, “It must be more important to be skilled
in thinking than to be stuffed with
facts4.” In the
context of science education, Biggs stated, “Rote learning
scientific formulae may be one of the things scientists do, but it is not the way
Some students believe that in science there are right answers
to everything and that the mastery of a particular body of
scientific knowledge allows one to become an expert in the
field. It is partly this belief that leads to public misconceptions
about what science can and cannot do. My own philosophy of
the goal of science education is certainly not original; but
in my mind, rather than purely adding to a student’s
existing store of knowledge, we should
be promoting science education as a way of thinking6.
Consequently if we are to help students learn, we need to
understand how students learn. We need to predicate our teaching
on enabling learning to happen. The literature on how people
learn is vast, but perhaps the most influential and accessible
theories of learning, and one that certainly strikes a chord
with me, is that of constructivism7.
Constructivism can be summarised in the phrase: “Knowledge
is constructed in the mind of the learner8.”
When we teach, we need to remember that the new facts that
we propound do not become directly incorporated into the mind
of the student without processing; they have to be fitted
into the existing structures and schemata already in the mind
of the student. For the learner faced with new information,
the only thing that matters is whether the knowledge constructed
from this information functions satisfactorily in the context
in which it arises.
Thus, individuals may construct different images of reality
from the same information, since each is incorporating the
new information into a unique set of mental images. This of
course explains why students frequently seem to misunderstand
completely or fail to remember new concepts that we introduce
to them. If we are to enable students to learn, we must accept
that we cannot brilliantly transfer into the minds of our
students, what we have in our own minds. As a guide to help
teachers teach, Ausubel stated that:
If I had to reduce all of educational psychology to one
principle, I would say this: the most important single factor
influencing learning is what the learner already knows. Ascertain this and teach him accordingly9.
In applying these ideas to science teaching, it is worthwhile
considering that our minds do not contain reality itself,
but models of reality that we have constructed. It is important
to impress upon students, who can appear to be unaware of
the fact, that their concepts of, for instance, atoms and
molecules, are only models. Simple models of reality provide
a strong framework for a student to incorporate new ideas
and so construct a more complex model. It maybe that the final
model that we wish our students to understand will require
us to help students construct several intermediate models.
Of course the ability of a student to construct a new model
of reality is influenced not only by their prior knowledge, but also by the level
of intellectual development that the individual has reached.
Piaget7, the author of
constructivism, gave a useful scheme of intellectual development.
His research showed that children progress from ‘pre-operational
thought’ to ‘concrete operational thought’
and finally through to ‘formal operational thought’.
The last two levels are relevant to higher education. Concrete
operational thinkers argue from concrete examples; typically,
they can describe without explaining, and give examples but
not general definitions derived from these examples. Formal
operational thinkers, in contrast, can follow a formal argument,
can set up hypotheses, and are comfortable
with hypothetico-deductive reasoning10.
However, it is perhaps not the progression of intellectual
development that is relevant to higher education, but the
fact that students will revert to concrete operational thought whenever they encounter a new area11.
Before one can reason with hypotheses and deductions based
on experience, there must be a sound descriptive base that
has been put in order. The problem for teachers is that we
are frequently expounding to students new topics with which
we are very familiar (and consequently operate in formal operational
mode) whereas the students are struggling to understand them
in concrete operational mode, and necessarily resort to rote
learning. If a student remains a concrete operational thinker
within a particular topic, it is difficult (although not impossible)
for that student to see the inter-connectivity between different
topics that a complete understanding of a science demands.
Traditionally, laboratory experiments have been essentially
expository-type exercises. Unfortunately, most students try
to keep the time they think about practical work to a minimum.
The basic design of a laboratory experiment is one where the
students are asked to follow a set of instructions, a recipe
if you will. This enables the students to complete an experiment
without ever thinking about what they are doing, thus militating
against any meaningful learning taking place. It is widely
appreciated that there is a need for an inquiry-type dimension
to the laboratory experiment. A few innovations have been
introduced to the laboratory setting. These
include pre-laboratory exercises12 to encourage students to think about the experiment they
are about to perform, and post-laboratory exercises13 to facilitate reflection and promote consolidation of learning.
In this article, I would like to concentrate on my experiences
within the laboratory class. It would be remiss of me not
to mention at least a couple of issues that relate directly
to my experiences in Singapore. The laboratory classes at
NUS are blessed by Teaching Assistants, who at least in my
experience, are diligent and hard working. However, this diligence
can sometimes play into the hands of students who are trying
to minimise their own diligence. By and large, experiments
work and students know they work. Some students, on realising
that an experiment is failing, will not attempt to discover
the reason behind this, but instead expect the Teaching Assistants
to fix the experiment. Some Teaching Assistants themselves
compound this issue by standing over the students and stopping
an experiment if they see that the data coming out are going
awry. It took me awhile to realise what was happening for
the lingua franca between the majority of the teaching assistants
and the majority of the students is Chinese of which I have
no understanding. An issue that was my responsibility, and
the effects of which are completely opposed to my teaching
philosophy, is that I allowed the students to write laboratory
reports after class. Frequently, the experiments are classics
of their type and detailed descriptions of the theory and
the results that one might expect can be found in standard
textbooks. It is singularly difficult to motivate students
to rediscover this knowledge for themselves, rather than copy
it verbatim from a textbook. I will not be allowing this practice
to be repeated in future classes I supervise.
Within the laboratory class, it was clear that if I wanted
any meaningful learning to take place, I had to become directly
involved in the learning process. So I employed Socratic questioning.
For me, this method works because in questioning the students,
I gain an insight into their current level of knowledge from
which I can then help guide the students construct the necessary
more complex model they require to understand the concept
at hand. It also allows me to help the students identify the
fundamental principles and the links between diverse concepts.
For the student, I believe it helps build confidence. I can
introduce concepts at a rate dependent on the student’s
ability, and thus, the student feels inclined to venture into
areas of higher understanding where such a student may have
been embarrassed to venture in a tutorial setting with that
student’s peers looking on. In increasing the student–teacher
interaction, the student gets full and appropriate feedback.
I find that after helping a student construct the requisite
knowledge, that student is inclined to ask questions about
their newfound knowledge. This has the additional benefit
of highlighting any misconceptions I may have introduced.
If feedback to these questions is given appropriately with
the proper encouragement, then that student’s confidence
and motivation is increased. However, I would not like to
give the impression that this method is some sort of panacea.
For instance, I was fortunate that the class sizes were small.
This is not the norm. Many laboratory classes can number a
hundred or more and then the attention that one can give individual
students is limited and the method of teaching would need
to be modified.
I have been rather liberal in my use of quotations during
this discourse. However, I hope that they have been useful
in illuminating the concepts that I have introduced and my
thinking concerning teaching. In conclusion, I would like
to leave you with a final quotation that returns us to why,
how and what we are trying to teach to our students. In 1929,
the eminent philosopher and mathematician Whitehead turned
his thoughts to education and wrote:
In my own work at universities I have been much struck
by the paralysis of thought induced in pupils by the aimless
accumulation of precise knowledge, inert and unutilised.
It should be the chief aim of the university professor to
exhibit himself in his true character—that is as an
ignorant man thinking, actively utilising this small share
of knowledge. In a sense, knowledge shrinks as wisdom grows:
for details are swallowed up in principles. The details
of knowledge which are important will be picked up ad hoc
in each avocation of life, but the
habit of the active utilisation of well-understood principles
is the final possession of wisdom14.
It is clear that motivating students to think has been an
elusive goal of educators for a very long time.
1 Haldane, J.B.S. (1923).
Daedalus, or Science and the Future. London: Kegan Paul, Trench,
Trubner. This paper was read before the Cambridge Heretics,
a radical freethinking society established in 1909 and dedicated,
inter alia, to the open discussion of religious matters.
2 The laboratory class
provides perhaps some of the earliest examples of problem-based
learning. In fact, von Liebig at the University of Giessen
in Germany first introduced laboratory classes for general
student use as early as the 1820s.
3 Byers, W. (2002). ‘Promoting
Active Learning through Small Group Laboratory Classes’.
University Chemistry Education. Vol. 6, pp. 28–34.
4 de Bono, Edward. (1967).
The Five Day Course in Thinking. London: Penguin.
5 Biggs, J.B. (1989).
‘Approaches to the Enhancement of Tertiary Teaching’.
Higher Education Research and Development. Vol. 8, No. 1,
6 Kuhn, D. (1993). ‘Science
as Argument: Implications for Teaching and Learning Scientific
Thinking’. Science Education. Vol. 77, No. 3, pp. 319–337.
7 Piaget, J. (1926). La
représentation du monde chez l’enfant, Paris:
Librairie Félix Alcan. Translated as The Child’s
Conception of the World by Tomlinson, J. & Tomlinson,
A. (1929). London: Kegan Paul, Trench, Trubner.
8 Bodner, G.M. (1986).
‘Constructivism: A Theory of Knowledge’. Journal
of Chemical Education. Vol. 63, pp. 873–878.
9 Ausubel, D.P. (1986).
Educational Psychology: A Cognitive View. New York: Rinehart
and Winston, Inc.
10 For example, we can
consider gravity. People have always known that what goes
up must come down. Concrete operational thinkers can describe
the force of attraction between objects and of course give
diverse examples. However, prior to the publication of Newton’s
Principia Mathematica, we did not have a working hypothesis
for why the apple falls from the tree towards the Earth; instead
it was considered a Law of Nature. In developing his theory
of gravitation, Newton asked why do objects fall towards the
Earth. It is the asking of this question that contrasts the
concrete with the formal operational thinker. The brilliance
of Newton’s theory was not that it explained why objects,
like the apple, fall towards the Earth, but that it explained
the ocean tides, why the Moon orbits the Earth and why the
Planets orbit the Sun.
11 Bailey, P.D. &
Garratt, J. (2002). ‘Chemical Education: Theory and
Practice’. University Chemistry Education. Vol. 6, pp.
12 Johnstone, A.H.; Sleet,
R.J. & Vianna, J.F. (1994). ‘An Information Processing
Model of Learning: Its Application to an Undergraduate Laboratory
Course in Chemistry’. Studies in Higher Education. Vol.
19, pp. 77–88.
13 Johnstone, A.H. (1997).
‘Chemical Education, Science or Alchemy?’. Journal
of Chemical Education. Vol. 74, pp. 262–268. Ditzier,
M.A. & Ricci, R.W. (1994). ‘Discover Chemistry:
Balancing Creativity and Structure.’ Journal of Chemical
Education. Vol. 71, pp. 685–688.
14 Whitehead, A.N. (1929).
The Aims of Education and Other Essays. New York: Macmillan.
The chapter, ‘The Rhythmic Claims of Freedom and Discipline’,
from which the quotation was lifted was originally published
in the Hibbert Journal.