Practical Work - The Laboratory

Labs
Postscript
Portable Document Format

Most would agree that students, in order to learn new skills, reinforce concept understanding and to experience the scientific method, should undertake practical work. The references, presented here, reflect a desire to improve the effectiveness of the laboratory experience.

General Papers

Johnstone and Al-Shuaili 2001

Johnstone, A. H. and Al-Shuaili, A, Learning in the Laboratory: Some Thoughts From the Literature. University Chemistry Education, 5, 42-51, 2001.

This paper presets a brief overview of the literature relating to laboratory work, including, the purposes of laboratory work, teaching strategies (including how they relate to the purposes) and laboratory assessment.

Yang and Aitkinson 1998

Yang, M. J. and Aitkinson, G. F, Designing New Undergraduate Experiments. Journal of Chemistry Education, 75(7), 863-865, 1998.

This paper offers general questions and checklists, based on experience and observation, to aid new instructors in the development of new undergraduate experiments.

Laws 1991

Laws, P. W., Calculus-Based Physics Without Lectures. Physics Today, 44(11), 24-31, 1991.

This article describes ``Workshop Physics'': a laboratory based introductory physics course. Although not suitable for large classes the author reports that elements of the course have been adapted for use in universities. Sample exercises from a Workshop unit are presented.

Browne and Blackburn 1999

Browne, L. M. and Blackburn, E. V., Teaching Introductory Chemistry: A problem-Solving and Collaborative-Learning approach. Journal of Chemistry Education, 76(8), 1104-1107, 1999.

This paper describes the development of a problem based introductory university organic chemistry course, centred in the laboratory. [Group]

Practical Work: Problems Experienced by Students

Johnstone and Letton 1990

Johnstone, A, H, and Letton, K. M, Investigating Undergraduate Laboratory Work. Education in chemistry, 27(1), 9-11, 1990.

In this investigation, 24 students were given a diary to record their experiences in a second year University chemistry laboratory. Analysis of these diaries identified problematic experiments. Experiments found to be difficult contained a disproportionately high content of theory thus creating a possible information overload: resulting in recipe following. The authors suggest that ``most of the learning (if any) takes place at the reporting stage when the student reviews what has been done and tries to interpret the results''.

Johnstone and Letton 1991

Johnstone, A. H. and Letton, K. M., Practical Measures for Practical Work. Education in chemistry, 28(3), 81-83, 1991.

Reports that the experimental instruction and observational load, encountered by students in the laboratory, results in recipe-following or observation recording with very little interpretation or understanding. To remedy this the authors advocate the following actions:

• reduce noise in the instruction manual.
• foster confidence in the use of laboratory equipment, by introducing a carefully thought out skills programme.
• use pre-labs.
• use post-labs.

Johnstone and Wham 1982

Johnstone, A. H. and Wham, A. J. B, The Demands of Practical Work. Education in chemistry, 19(3), 71-73, 1982.

In this paper the diagram of Figure 6.1 is presented which is used to represent the experience of laboratory students.

Figure 6.1: Unstable overload in practical work. View a Larger Image Here

The authors recognise that ``during the learning phase, the student is in no position to distinguish between `signal' and `noise''', and as such they present teaching strategies and improvements in experimental design to reduce the `noise'.

Johnstone and Wham 1979

Johnstone, A. H. and Wham A. J. B., A Model for Undergraduate Practical Work. Education in chemistry, 16(1), 16-17, 1979.

Here the authors suggest that in practical work ``there is insufficient emphasis on the mastery of skills to a high level'' and that the ``student is `programmed' too much and takes on little responsibility for his own learning, and so thinks little for himself''. To overcome these weaknesses they propose the inclusion of experimental units which are composed of two sections:

• firstly a taught period in laboratory skills
• secondly a period in which students use their newly learnt skills to investigate a practical problem with the minimum of help or instruction.

This philosophy is illustrated and evaluated with a real example, and the students' attitude to this form of practical work is reported.

Johnstone et. al. 1994

Johnstone, A. H., Sleet, R. J. and Vianna, J. F., An Information Processing Model of Learning: Its Application to an Undergraduate Laboratory Course in Chemistry. Studies in Higher Education, 91(1), 77-87, 1994.

This paper details and evaluates changes to a first year undergraduate chemistry laboratory. Changes were based upon hypothesis derived from an analysis of the information processing model of learning, Figure 6.2. Changes included, re-writing of instructions manuals, re-organisation of the laboratory, the use of pre-labs, training in laboratory skills and the introduction of mini-projects. The authors state that ``[their] study supports the conclusion that the changes were effective in improving students' attitudes about the laboratory course''. Moreover, ``the changes in student attitude and outlook, brought about during this study, are entirely in accord with the predictions inherent in the [information processing] model'', See Section 14.5

Figure 6.2: Information Processing Model of Learning. View a Larger Image Here

Using Pre and/or Post Labs

Cox and Junkin 2002

Cox, A. J. and Junkin, W. F., Enhanced Student Learning in the Introductory Physics Laboratory. Physics Education, 37(1), 37-44, 2002.

In this paper the authors suggest that, where students experience confusion or supply alternative concepts to explain experimental results, laboratory work be augmented by conceptual questions. The effectiveness of this approach was assessed using pre and post labs. The authors conclude that our ``results are based on a relatively small data sample, but they do show that embedding questions in the laboratory, asking students to submit these answers real time to the instructor and then occasionally pairing groups across the lab enhances student learning''.

Johnstone et. al. 1998

Johnstone, A. H., Watt, A and Zamen, T. U., The Students' Attitude and Cognition Change to a Physics Laboratory. Physics Education, 35(1), 22-28, 1998.

Another study into the use of pre-labs, this time in the physics laboratory. Includes a discussion of cognition, and the role of the short and long term memory on the learning of new material. They found that the use of a ``pre-lab fostered a positive attitude in the students toward the changes made in the physics laboratory'' and that ``understanding of the physics practical work improved''. They also report a large improvement in post-lab work by, those students using pre-labs prior to starting an experiment. An example of a Pre-lab, ``mechanical oscillator and resonance'', is presented in the appendix.

Meester and Maskill 1995a

Meester, M. A. M. and Maskill, R., First-Year Chemistry Practicals at universities in England and Wales: Aims and the Scientific Level of the Experiments. International Journal of Science Education, 17(5), 575-588, 1995.

This survey of 17 university practical classes is concerned with the aims and objectives of practical work, the scientific level of the experiments and the laboratory skills being taught. Differing instructional methods and the relationship between aims and teaching methods are also discussed. In their conclusions they mention that first year undergraduate practical work is heavily based on recipe-following with little attention paid to skills teaching: ``students probably learn quite a lot about practical work but probably do not learn too well how to do it, with any skill, speed or efficiency''.

Meester and Maskill 1995b

Meester, M. A. M. and Maskill, R., First-Year Chemistry Practicals at Universities in England and Wales: Organisational and Teaching Aspects. International Journal of Science Education, 17(6), 705-719, 1995.

In this follow-up to their earlier paper (Meester and Maskill 1995a), the authors focus on the format of practical classes, the timetable, use of electronic media, the manual and assessment methods. Having cited the literature, which presents possible improvements to laboratory work, the authors "conclude that first-year practical courses in England and Wales have changed vary little over the preceding 15 years.''

Domin 1999

Domin, S., A Review of Laboratory Instruction Styles. Journal of Chemistry Education, 76(4), 543-547, 1999.

Identifies four laboratory instruction styles differentiated by three descriptors, see Table 6.1, and provides an overview (with references) of each style

Table 6.1: Descriptors of the Laboratory Instruction Styles

	Description
Style	Outcome	Approach	Procedure
Expository	Predetermined	Deductive	Given
Inquiry	Undetermined	Inductive	Student Generated
Discovery	Predetermined	Inductive	Given
Problem-Based	Predetermined	Deductive	Student generated

Expository

Traditional - ``cookbook'' style.

Inquiry

Given an assignment the students decide the system to investigate, design their own experiments, and collect and analyse their own data.

Discovery

Guided inquiry to aid ``discovery'' of the desired outcome.

Problem-Based

Students are presented with a problem with a clear goal to which they must devise a procedure that will lead them to a solution.

Also reviews the current state of research into the effectiveness of each style. Suggests that additional research is necessary before any conclusions can drawn.

DeMeo 2001

DeMeo, S., Teaching Chemical Technique: A Review of the Literature. Journal of Chemistry Education, 78(3), 373-379, 2001.

This review presents ways in which chemistry laboratory skills can be taught, discusses various types of pre-laboratory exercises and looks at how mental practice can be used to improve the acquisition of motor skills.

Wright 1996

Wright, J. C., Authentic Learning Environment in Analytical Chemistry Using Cooperative Methods and Open Ended laboratories in Large Lecture Courses. Journal of Chemistry Education, 73(9), 827-832, 1996.

Here the author presents the elements of an analytical chemistry course in which the first half is used to provide students with the necessary skills and knowledge base such that, in the second half, they can undertake a collaborative open-ended laboratory project. Naturally the outcomes are all positive. [Group]

Vianna et. al. 1999

Vianna, J. F., Sleet, R. J. and Johnstone, A. H., The Use of Mini-Projects in an Undergraduate Laboratory Course in Chemistry. Quimica Nova, 22(1), 138-142, 1999.

In this paper the authors report on a three year study into the use of mini-projects. These require students to use knowledge and skills, (supposedly) developed in previously completed set laboratory experiments, to solve a short practical problem. Examples of mini-projects and a number of recommendations related to their use are given.

Problem Based Learning (PBL)

Duch et. al. 2001

Duch, B. J., Groh, S. E. and Allen, D. E., The Power of Problem-Based Learning: A Practical ``How To'' For Teaching Undergraduate Courses in Any Discipline. Sterling, Virginia: Stylus Publishing., 2001.

The Problem-Based Learning (PBL) pedagogy uses real world problems to motivate students to identify and apply research concepts and information, work collaboratively and communicate effectively. This book, written for college and university faculty, focuses on the practicalities of setting up a PBL course.

Ram 1999

Ram, P., Problem-Based Learning in Undergraduate Education. Journal of Chemistry Education, 76(8), 1122-1126, 1999.

Gives a brief introduction to Problem-Based learning (PBL) and then presents ``The Water We Drink'' an example of problem based learning successfully incorporated into a Second year university chemistry course. The authors found that when students are presented with ``an authentic problem that is challenging and real, they will be motivated to learn and to enjoy the learning process immensely''.