Online Biology Pre-Labs
"Student reads lab manual prior to class. Unusual move stuns professor, classmates."
This simulated newspaper headline, greeting students on the Biology Concepts Laboratory course Web site at Western Kentucky University, points out a common dilemma in college science laboratory courses. Too often students arrive at the laboratory totally unprepared.
It is no secret that many freshmen arrive at universities with less than ideal study habits. These same students are frequently surprised at the amount of homework and pre-class preparation required for College classes, especially in comparison with their previous experience.
The special challenge of teaching science laboratories is to ensure that students prepare in advance, so that they can explore the concepts rather than struggle with the details of the protocol. Many introductory science lab exercises have a cookbook format. D'es this sound familiar? Put 5 ml from tube A into tube B, record the color change … This, and the less-than-exciting prose of most science lab manuals make science lab classes ideal targets for procrastination and neglect by students. To a veteran instructor, the students who have not read the lab manual prior to class are obvious, for their attention is on the measurements, mechanics, and manipulations of the experiment, their focus on the "change in color" and where to record the data. They may completely overlook the biological or chemical principles they are meant to investigate.
The Digital Science Prelab
You could surmise that this is why the "Prelab" was created. The concept
of Prelab exercises is an old one. Many, if not most, introductory college chemistry
laboratory courses require handwritten (or more recently, download and complete)
outlines of lab procedures or flowcharts that often include sample calculations
as a Prelab. The intent is simple: to ensure the student has read the material
prior to attending lab and can successfully complete the experiments or exercises.
Several colleges and universities have taken the next steps in education tools for science laboratory classes. Digital Laboratory Manuals, digital videos of laboratory techniques, and interactive Prelabs are not uncommon. The intent of most of these projects is to supplement—not replace—the traditional lab exercises and to prepare the students for the lab exercises using simulations, animations, images, and videos.
The Biology Concepts Laboratory Prelabs at Western Kentucky University are a series of interactive online lab exercises and simulations that are designed to address the preparation problem in an interactive way. The project’s goals were to improve the students' experiences in the laboratory, familiarize them with the equipment and data analysis involved in the experiments, and thus allow them to focus on the biological principles underlying the experiments rather than on the manipulations.
In this project, all units either have multimedia simulations of activities performed in the exercises, or tutorials and quizzes that are submitted and graded prior to coming to lab each week. The Prelab exercises make extensive use of graphics, Flash animations, and Interaction through Active Server Pages. The result provides students with a virtual version of the laboratory experience as preparation and enhancement of the real lab exercises. The students must still come to the lab, hear an introduction, and perform the experiments.
The Prelabs are tightly connected to the actual laboratory manual. In fact, the procedures in the virtual experiments are nearly identical to the lab experiments. The Prelab units include three on Macromolecules, Use of a Spectrophotometer, DNA isolation, Osmosis, Enzyme Activity, Photosynthetic Pigment Chromatography an Chloroplast Isolation, Cellular Respiration, Mitosis and Meiosis, a Chi-Square Analysis of Corn Genetics, as well as a Hardy-Weinberg analysis of protective coloration data. These are very standard general biology labs. In most of the Prelab exercises, the students collect or generate data and perform statistical analyses as they will do in the actual lab. All the exercises have self-grading quizzes and a receipt page is provided upon completion of the Prelab for the student to present to their lab instructor.
Satisfied Students
A student survey offered after completion of the course each semester indicated
near unanimous satisfaction (more than 95 percent of about 300 students) with
the Prelab exercises. This was a little surprising considering extra time and
work had been added to the students’ educational "burden." The students
indicated that they thought using the Prelabs probably improved both their lab
skills and their grade. In particular, they felt that Prelabs prepared them
for the practical aspects of laboratory sessions and the interactive quizzes
gave them better feedback prior to lab. While the preliminary data have failed
to show any statistical difference in learning outcomes between students who
used the Prelab and students who did not, student satisfaction is a worthy result
in and of itself.
A few typical (truly) positive comments follow:
- "I thought that the Prelabs were a big help in learning more about
the lab before we had to actually do it, and also it made me read the lab
before I came to class."
- "I'll admit, sometimes I dreaded taking the time to do the pre-lab,
but after the first few, I realized what a HUGE help they were in preparation
for the quiz and for our knowledge in performing the lab. I think it's a great
idea and very helpful to those who actually take the time to read it. Thanks."
- "I honestly think that it helps to visually see things in the pre-labs
prior to actually doing them."
- "I found the Prelabs to be very helpful when I studied for my first
test. I redid every one of them and finally understood what all the rest of
the material was saying."
The data the students generated, quiz scores, and some other demographic information are captured in a "back-end" for monitoring Prelab functionality and improving the exercises. Many of the students repeated the Prelab until they scored full marks. We allow the Prelab exercises and the quizzes to be repeated indefinitely, since the primary purpose of the Prelabs is preparation and mastery.
A Frequent Lament
One prevalent, and again surprising, comment was that the Prelab exercises were
too much like the actual labs. Many students felt performing the lab exercise
was redundant and unnecessary after completing the Prelabs. Comments like these
form the basis for our willingness to consider and attempt the next step, wholly
online lab exercises.
- "The Prelab tells you exactly what you are doing in the experiment which
made me feel that I was wasting my time during the actual lab."
- "I think that it would help to gain experience in the lab if the Prelabs
weren't exactly the same as the labs in class."
- "After doing the Prelabs, there is no real reason to come to class. We go
in and do a lab that is exactly like the computer."
- "The Prelabs were very helpful, but I don't think doing the Prelabs
and then going to class and completing the exact same lab was very helpful.
I already knew what was going to happen so I didn't want to watch and do it
again."
The Completely Online Lab
We are currently developing virtual lab exercises based on our experience with
the online Prelabs. We are convinced that, especially for non-science majors,
well-designed online labs can completely substitute for the "real thing." For
non-science majors, understanding experimental design and data interpretation
are more important than learning to manipulate a particular scientific apparatus.
For science majors, the situation is different. Hands-on lab experience can be very important, for there are many significant science concepts found in the experimental manipulations themselves. For majors, online Prelabs should be used to prepare them so that their actual laboratory experience can be enhanced. For the science students as well, online preparation should free time from the details and allow for probing and investigating beyond the initial lab manual experiments.
A student expressed this concept as follows:
"I liked the Prelabs because it
helped me know what to expect when I came into lab. At the same time I kind
of felt as though the prelabs made lab experiments unnecessary because we already
knew what to expect for all the results. In my opinion the labs would be much
more enjoyable if the results we were to get were somewhat unexpected. Perhaps
if there was a prelab to explain the experiment and then other experiments to
do in lab, students would retain more info from the lab and be more likely to
pay attention during their lab time."
Instructors in more advanced biology classes may also find that introducing and reviewing concepts in a Prelab and then following with investigative experiments in the actual lab would be advantageous to stimulate scientific discovery in students.
We plan to use the information gained from the student comments and survey to refine how online Prelabs can help us facilitate the best educational experience for all levels of students.
The Biology Concepts Laboratory Prelabs at WKU are freely accessible at http://bioweb.wku.edu/courses/Biol121/Prelabs.htm
and are listed and reviewed at the MERLOT Web site: www.merlot.org.