CAUT Report

UniServe Science News Volume 8 November 1997

An Integrated Video and Practical Program for Teaching Microscopy

Introduction

For students of biology, mastery of the compound light microscope is probably the single most essential technical skill they must develop and use consistently throughout their training. A 1996 survey of first year biology science students at La Trobe University (conducted by us to ascertain the entry level skills of the first year trial class) indicated that 94% of the students had used a compound microscope before coming to university, but of these, 85% felt that they had had no, little or at best superficial instruction in microscopy. Furthermore, estimates of functional and procedural knowledge of microscopy technique substantially supported these findings.

In order to address this problem of skill deficiency, an intense small group teaching and learning program, using interactive video, was developed and implemented. Evaluative tools used for the program indicated not only improved knowledge of microscopy technique, but also, and more importantly, elevated manipulative skill levels.

The Program

The program focuses on the use of interactive video in small group teaching within the laboratory - a strategy adopted to maximize teacher interaction with students and akin to that used in secondary schools (important for the transition from secondary to tertiary levels of education).

The program is intended to achieve the following specific objectives:

• to instruct students in the correct use of the compound light microscope;
• to help students understand some of the basic principles of microscopy; and
• to help students learn how to solve simple problems encountered when using a microscope.

It is a fully integrated package of three video sequences punctuated by discussion and investigative exercises encompassing the principal areas of microscope use viz.

Part One: Introduction to Microscopy

This part comprises a video sequence with associated practical exercises which serves to provoke students' interest in microscopy, explain the basics of microscopy, and introduce the fundamental concepts of magnification and resolution.

Part Two: Use of the Compound Light Microscope

A video sequence and associated laboratory exercises elaborate the major components of a compound light microscope, their function and how to correctly adjust and use the microscope.

Part Three: Trouble Shooting in Microscopy

A video sequence provides an account of three commonly encountered problems in microscopy. Each problem is presented, followed by a hiatus for group discussion to resolve the problem. A solution is subsequently presented.

The above structure was adopted such that each part can be used independent of the other parts, depending on the time allocation and the level of instruction required.

An AUSLAN (Australian Sign Language) version of the program was developed in response to the increasing number of deaf students entering tertiary education.

Evaluation and Assessment

A preliminary evaluation of the program was conducted in 1995, in a second semester, first year course. The evaluation was repeated in 1996 after implementation in first semester. Evaluation of competence levels was conducted over the semester. Essential to this evaluation were opportunities for feedback and remedial work until students achieved a specified level of performance.

Evaluation of student competence levels comprised:

• direct observation by teaching staff - an observation checklist was compiled for each student;
• practical test under teacher supervision;
• questionnaire; and
• self-assessment.

Evaluation of the program occurred at three levels, viz.

• teaching staff,
• students,
• the project reference group,

Results

Evaluation of Student Skills
Of the ten manipulative skills evaluated by the observation checklist, five had competency levels above 90%, and of these, four were considered 'primary skills', that is, essential for successful examination of a specimen. Competency levels for the other five skills evaluated ranged from 53% to 73% and diagnosed deficiencies in microscopy skill development which will require greater emphasis in future strategies for skill development and instruction.

Entry and exit skill levels for knowledge and comprehension of microscopy was determined for all students. In all of the questions posed there was a statistically significant increase in skill level (Figure 1).

Figure 1. Percentage of Correct Answers to Knowledge Questions Before and After Microscopy Program

The 1996 survey proved invaluable as a diagnostic tool and detected several deficiencies in the knowledge base of students. These results were in accord with the manipulative skill deficiencies exposed by the observation checklist, supporting the case for modifications to the instructional emphasis of the program.

During first semester 1996, second year students enrolled for the B.Sc. (Biological Sciences) were surveyed with the same seven questions as the 1995 first year survey to evaluate retention levels for knowledge and comprehension. A slight diminution occurred in only three questions (to 70%, 70% and 87% respectively). Improvements were noted for the other questions of the survey (Figure 2).

Figure 2. Percentage of Correct Answers at End of Program in First Year and in Second Year

The program was also integrated into the new Forensic Science Post-graduate Diploma at La Trobe. The students (graduates already employed in forensic sciences) showed a significant increase in knowledge (Figure 3).

Figure 3. Percentage of Correct Answers for Forensic Science Post-graduate Students

Evaluation of the Program
The teaching staff who participated in implementing the program endorsed the video - practical format with its attendant resource material, as an effective strategy for teaching and learning microscopy. Staff, particularly those experienced in teaching microscopy to first year students, found the checklist an effective strategy for monitoring and feedback.

All the staff supported maintaining the program for teaching and learning microscopy.

Students participating in the program were surveyed on the palatability and effectiveness of the program. In general the students endorsed the program indicating strong support for the level of integration of the resources and the medium used, the instructional value of the print material provided and the instructional value of the feedback strategy used by the teaching staff.

Implementation

The program has been fully integrated into the core curriculum for undergraduate studies for the degree of Bachelor of Science (Biological Sciences) at La Trobe University.

A promotional flier was sent to all universities in Australia and all secondary schools and T.A.F.E. colleges in Victoria.

The program has also been promoted via a WWW home page http://www.gen.latrobe.edu.au/microscopy/

The page has been listed on the Yahoo and Alta Vista search engines and over 1,300 'hits' have been made. This has resulted in enquiries from England, Belgium, America and Australia.

The package has been sold to Victorian secondary schools and T.A.F.E.s as well as Australian universities.

Page Maintained By: PhySciCH@mail.usyd.edu.au
Last Update: Monday, 30-Apr-2012 15:42:13 EST
URL: http://science.uniserve.edu.au/newsletter/vol8/hale.html