INTRODUCTION
Computer lecture presentations, u
sing software such as
Microsoft's PowerPoint, are becoming increasingly widely used in
college classrooms throughout this country. Judging from the
response in the classes taught by the author of this paper,
students are extremely enthusiastic about this type of
technology. Many faculty appear to be equally satisfied, as
evidenced by the fact that they are choosing to invest
considerable amounts of time and effort into revising their
courses.
Despite the rising popu
larity of presentation software, thus far
there has been very little evidence that this technology can
improve learning. This should not be surprising, since the
technologies have been used for a relatively short period of
time, and it is not yet clear how to maximize their usefulness.
It is probably true that learning to master the technology itself
is much easier than discovering the pedagogy that makes the best
use of the technology for learning.
For the past three y
ears, the author of this paper has enjoyed
considerable success using a combination of cooperative learning
and presentation software in his general chemistry classes.
Based on the research that has been done on the advantages of
multimedia presentations, it would appear that the combination of
these two approaches, even though it occurred by accident, is a
particularly valuable educational technique.
IMPLEMENTATION
In the fall of 1990, it had became clear t
hat student performance
in my general chemistry course was declining. Although the
failure and withdrawal rates had been relatively stable for a
number of years prior to this, these measures of student
performance had been decreasing significantly for the previous
three years. To counteract this trend, I implemented a revised
lecture plan combining cooperative learning with multimedia, such
as computer simulations, laserdiscs, and videotapes. This had the
desired effect of de
creasing withdrawals and failures.
The original plan was to present a short (10-15 minutes) lecture
segment, followed by a visual presentation, consisting of either
a live demonstration or a video (videotape, laserdisc, computer
simulation, etc.). Next I asked pairs of students (lecture
partners) to discuss and/or explain what they had seen using a
set of questions that I projected on the overhead. After
allowing time for discussion, I would call on individual students
and ask them to answer the questions. Often, when one student
answered a question, I would ask his or her lecture partner to
explain the answer. This insured that the students were
accountable for discussing the questions with their partners.
When the questions were completed, I began the process again with
another short lecture segment.
By the beginning of the 1994 academic year, I had experimented
with several different ways to present lectures from the
computer, inc
luding hypertext, a word processor, and presentation
software. Based on these experiences, I determined to use
PowerPoint, and during the 1994-95 year I revised my notes. This
approach has proven to be extremely successful, as will be
discussed below. Three articles are available that describe the
progress of this work (Pence 1993, 1996, and 1997).
PowerPoint allowed me to continue many of the techniques I had
been using with the overhead projector. Previously I showed a
script of questions for each cooperative exercise. As each
question was discussed, I would slide down a cover sheet to
reveal the correct answer. This type of validation is especially
important for successful cooperative learning. Of course, the
ultimate goal is to give students the confidence to trust their
own opinions, but initially students need to be reassured that
they have obtained the right answer. The build function in
PowerPoint accomplished the same goal very well. I
f the
questions are written on the title space, a careful alignment of
the text body makes it possible to reveal each answer right
beside the question.
PowerPoint also made it very easy to maintain the color coding
that I had used on the overheads. Key ideas were written in red;
green text was used to designate the cooperative exercises, and
white or yellow was used to present the main body of material.
Students found this approach to be especially useful, and
an
ecdotal evidences indicates that students continue to use color
coding in other classes as an effective method for recognizing
the important material in their notes.
As Neil Postman points out (1992), every new technology has
pluses and minuses. Wise technology implementation focuses not
only on what the new technology will offer but also on what may
be lost when the old methods are abandoned. The addition of
PowerPoint lectures maintained much that was good from the
pr
evious presentation methods and also provided new capabilities
that were very exciting.
ASSESSMENT
Continuing student assessment, both formal and informal, is a
vital part of the multimedia development process. The instructor
can never allow himself or herself to become so engrossed in the
technology that instructional problems are overlooked. Several
methods of assessment were used, ranging from informal
discussions with students through anonymous surveys t
hat were
administered at least twice a semester. Often the surveys
focused on issues that have been mentioned during the informal
interviews.
The combination of multimedia and cooperative learning has proven
to be consistently popular with the students. For example, in
the fall, 1996 survey, student response to the statement, "The
combination of hearing about a concept, seeing a demonstration,
then talking about it seems to be the best way for me to learn,"
was 60% strongly agree, 38% agree, 2% neutral and none of the
students checked disagree, or strongly disagree.
Informal student comments also demonstrated the popularity of
multimedia. In a number of cases, students stopped after lecture
to comment on how much they had enjoyed the videos and movies.
For example, when I showed a video of the burning of the
Hindenberg to demonstrate the properties of hydrogen gas, four or
five students stopped to say how much they were imp
ressed by the
movie. Similarly, the first time that I showed a short movie on
molecular rotation in class, the students were so fascinated that
they asked that the movie be repeated. It is very unusual to
obtain this level of response with even the best projecturals.
Although the student reaction to the use of presentation software
was not particularly favorable the first semester that I used it,
each semester since then eighty to ninety percent of the students
have indi
cated that they preferred or strong preferred
PowerPoint. There are several possible explanations for these
improved responses, the most important of which is probably the
fact that I learned to use the technique better.
Informal student comments on presentation software were also very
favorable. The images included in the notes were especially
popular, and many students commented that they associated the
concepts with the images in order to remember the concepts
better
. I did not distribute copies of the notes to the
students, but many students accessed the copies of the
presentations that were available on computers at the
chemistry/physics computer center.
DISCUSSION
It is interesting to examine the reasons that students gave for
preferring computer presentations. Three of the most often cited
reasons were legibility, organization, and the use of color
coding to indicate the relative importance of the material. Even
though it is true that PowerPoint, or any other presentation
software, does make it more likely that notes will be presented
legibly, that the material will be well organized, and that
important information will be flagged by the use of color, none
of these really requires the computer. Faculty were presenting
clear, well-organized notes, highlighted in colored chalk on a
blackboard, long before the computer was available.
The unique feature of PowerPoint is the ability to
closely
integrate text and images. The educational power of images is
well established. Although there is disagreement about the
mechanism, educational psychologists seem to be in agreement that
pictures improve the ability to remember text, especially if the
pictures and text are presented together (see references in
Kulhavy, R.W. et al, 1993). Mayer and Anderson (1992) have
obtained research results that show the importance of contiguity,
that is, the text and the images m
ust be presented
simultaneously. PowerPoint makes it possible to combine text and
images on the same frame and so should offer many students a more
effective environment for increasing the possibility for
remembering concepts than the use of text alone.
Shortly after I began to use PowerPoint, I realized that students
were taking a longer time to record their notes than I might have
expected based on my past experience with overhead projecturals.
When I questioned my s
tudents about this, I was surprised to
discover that many of them were copying both the text and a
sketch of the images into their notes, even though I had not
suggested that they should do this. During informal interviews,
a number of my students, including some who did not attempt to
include the images in their notes, reported they used the images
to help recall the concepts.
Images are be an especially important part of chemistry (Kleinman
1987). Chemistry is dynamic;
molecules are constantly moving,
even when they are not reacting. In the past, aside from an
occasional movie or demonstration, lectures about chemistry have
mainly been static. When the presentation technology is combined
with molecular modelling software, it is now possible to show how
chemical reactions happen, both at the macroscopic and the
molecular level. Beyond this, historical images can offer a
context for historical references that in the past might have
simply pa
ssed over the heads of the students.
Even though PowerPoint does make it possible to present
contiguous text and images, this provides no guarantee that
students will use this capability effectively. Obviously the
teacher must select images that are closely related to the
concepts being presented. Unless the images complement the text,
there is little possibility for interaction. Beyond this, what
can the instructor do to maximize the educational benefits of
combining i
mages and text on the same frame?
Presentation software does create an image-rich teaching
environment, but this can create problems. There is a tendency
for students, based on their previous experience with television,
to become passive observers, rather than active participants.
For example, Casanova and Casanova (1991) reported that their
students encountered problems of this type when taught with
multimedia.
Cooperative learning methods can help to avoid these
difficulties
and so are an excellent complement to PowerPoint lectures. It is
well know that cooperative methods are an excellent way to make
the students active participants in the learning process and when
used with appropriately designed scripts of questions this
approach can also encourage effective interaction between text
and graphics. The combination of PowerPoint with lecture
partners, as described earlier, seems to accomplish this quite
well, and no doubt other types
of cooperative learning would also
be effective. When the two teaching methods are combined, they
create an especially effective educational environment.
CONCLUSIONS
The new educational technology represents a special challenge to
the current generation of college teachers. Traditionally, most
college teachers have basically taught the way they had been
taught when they were students. As a result, change in teaching
has been incremental at best. Now teacher
s are being called upon
to learn how to teach in totally new ways. Although much has
been learned about the learning process in the past decade, our
understanding is still far from complete. For the time being,
each individual instructor must follow the development of
educational theory, share the experiences of colleagues, and use
student evaluations to determine what will work best in his or
her classroom.
This lack of hard knowledge is particularly prevalent in the us
e
of images for instruction. Previously few faculty had a
convenient way to incorporate images into their lectures. Even
those who used slides or videos may not have completely
understood the best ways to use this visual material. Now
presentation software, like PowerPoint, allows for the creation
of lecture presentations that are not just rich in images, but
which bring together text and images in ways that have
significant educational benefits.
Images are widely r
ecognized to be powerful educational tools,
and PowerPoint makes it easy to add visual material to lectures.
All disciplines may not benefit equally from the enhanced use of
images for lecture, but there are many situations where the
synergy described here can be useful. Many professors like to
include historical references in their lectures, but many
students lack the background to fully understand the comment. My
experience has been that adding appropriate images to the
pre
sentation can not only make this historical allusions more
relevant but even produce strong reactions from students.
New tools require us to rethink our approach to the educational
process. Even though no single teaching method, with or without
technology, may be equally applicable to all educational
situations, the new technologies, including the combination of
PowerPoint with cooperative learning, open new possibilities for
the educational process. The real challenge is no
t to learn the
technology, but to find the pedagogies that use technology to
give our students an improved learning environment.
Perhaps the best summary is to quote the response that a student
gave on an anonymous survey:
With the computer, the concepts became real. They weren't
just notes on a piece of paper. You actually prove that
things happen and we don't have to just accept what you tell
us.
As long as technology creates the opportunity to offer this kind
of experience to our students, it is well worth pursuing.