Use of PowerPoint in science lectures

Introduction

Microsoft PowerPoint is a useful piece of presentation software that allows for the use of multimedia presentations in the classroom.

Method

In order to effectively use PowerPoint in a classroom of twenty or more students a suitable monitor or projection device must be available for students to view. A typical computer monitor is not nearly large enough for viewing by an entire class. In order to meet this need a grant was received to purchase a 27" XGA monitor and laptop computer from which to drive the presentations. This grant opportunity was afforded by the school district's technology committee who makes monies available each academic year.

The school also owns a few LCD projection devices that allow for the monitor image to be reproduced on a large screen (80" plus). I also own one of these projectors and take it to school on occasion. The LCD monitor is far more flexible in its use but comes at a substantially higher purchase and operating cost than the large monitor.

The first two major units of study were presented using traditional lecture augmented by the use of a chalkboard and overhead projector.

PowerPoint presentations were developed to introduce material in most units of an academic chemistry I course that is part of this study. Students were assigned to read each chapter before introduction in the class.

At the beginning of each unit introductory material is presented to the class. This usually takes two class sessions and is the foundation for the material to be studied for about 14 class sessions.

Evaluation

Although PowerPoint presentation take more time to prepare than notes for a chalkboard or overhead projector they have many benefits. These benefits include:

  • Guided notes - Guided notes can be printed from the presentation slides and reproduced for the class. This saves class time since students do not have to transcribe everything into their notebooks. Space is provided on each guided note page for students to clarify concepts, write down examples that are given verbally, and keep record of accompanying demonstrations.
  • Editing - Chaning these presentations is much easier than changing printed notes or overhead slides. Typographical errors are easy to correct and changes from year to year are made quite quickly.
  • Consistency. When lecturing with the aid of a chalkboard or overhead projector the teacher can skip or miss important issues. Once a presentation is created all material is presented linearly.
  • Online sharing - PowerPoint presentations can easily be changed into a web based slide show for viewing by students who are absent. With PowerPoint there is no need for students to copy notes from other students or from the teacher. All information is found online and these presentations are integrated into the MrFlint.com web site.
  • Ease of viewing - Overhead projectors require most or all ambient lighting to be turned off during use, reducing the amount of light available for students to take notes. The chalkboards in the subject school do not provide much contrast and vary in their readability depending on the neatness of the teacher's handwriting.

Reflection

I have found there to be many real benefits to using PowerPoint in Chemistry lectures. When students are absent from school I simply refer them to the class web site where they can either view.

I don't suppose that I'll use PowerPoint too often in the Physics I course I teach since it requires a great deal of board space to work out the often complicated problems inherent to physics. The concepts in chemistry can usually be described with words while concepts in physics are usually more mathematical and aren't easy to reproduce in PowerPoint.