The Pre-Lab as an Instructional Aid in Introductory College Zoology

Abstract

Many smaller colleges and universities face the problem of how to allow faculty members adequate time for scholarly activity and still maintain high-quality classroom instruction. This dilemma is particularly acute in undergraduate science departments that operate laboratories with minimal help from advanced students or in institutions where the philosophy prevails that a Ph.D. should be actively teaching in the labs. The problem may also confront schools that cannot expand their teaching staffs because of steady or slightly declining enrollments. Our department decided to take another look at our large, introductory courses with labs to determine if there was some way to save time and still ensure quality education. Our introductory zoology course required three hours of lecture and three hours of lab per week. We had as many as five lab sections serving up to 150 students. Because of the three-hour lab format, we were required to offer labs on more than one day each week. If we could reduce the lab from three to two hours per week, we would not only reduce faculty contact time, but also significantly reduce the lab preparation time because all five lab sections could be offered on the same day. In the three-hour lab format, we found that as much as thirty minutes were required to introduce the lab exercise and allow students time to read their lab manuals and become familiar with equipment and procedures. Three hours is too long to work continuously; and, consequently, breaks tended to consume another twenty minutes. Based on these observations, we concluded that one hour of lab could be omitted if the students began the lab work immediately and that the two-hour format would require little break time. To get students to prepare in advance for labs, we prepared an audio visual exercise they were to complete before coming to the laboratory. This pre-lab exercise was incorporated into our lab manual as a brief outline of topics discussed. It served as a guide for taking notes during the pre-lab session. The information in the pre-lab was only available from the tapes and slides. The purpose of the pre-lab was to bring each student up to the same level of knowledge and preparation before the lab started. We designed all of our own pre-lab exercises. Each consisted of an audio-tape and slides. The audiotapes were from 10 to 30 minutes long. A pre-lab introduced each exercise. Some background material was included, but the major part of the tape focused on introducing the use of instruments or techniques. For example, use of the microscope and the Spectronic 20 were in the pre-lab exercise and techniques for dissection were also covered. With the use of these pre-lab exercises five minutes or less were required for introducing the laboratory; this introduction largely dealt with the location of various materials to be used during that lab session. The pre-lab is administered by our Learning Resource Center. We have two sets of tapes and 2 x 2 slides; each tape player has four headsets so that a total of eight students can work simultaneously. We did not require students to attend the pre-lab exercises, but they were encouraged to do so because some questions from the pre-labs were included on tests.