Classroom Electronic Presentation beyond Powerpoint: Enhancing Conceptual and Quantitative Understanding

With the advent of Blackboard and library e-reserve services, college students have come to expect electronic delivery of course content. While this generally means Powerpoint slides to illustrate lectures, with both drawbacks and benefits, there are also other pedagogical opportunities created by the use of digital information presented via a laptop and projector in the classroom. These opportunities extend from very large classes to smaller numbers of students, and from introductory classes to advanced graduate courses. Among the techniques to which students have responded well are the use of animations in both laboratory and lecture settings, and the use of spreadsheets to illustrate the role of variables in complex equations, and basic numerical methods.

Poorly conceived Powerpoint presentations using only “bullet points” have been criticized for their inadequacy in conveying information. However, use of a limited number of slides with graphical information or imagery and minimal text, combined with ample instructor explanation and elaboration, is more effective. It also builds on the exceptional reliance humans have on their visual perception for absorbing information. Electronic presentation also allows explanation of complex processes using animations that are increasingly available on the internet. Examples include the operation of a combined sewer system in wet weather when overflow to nearby water bodies occurs, and simple models of the magnetic or gravity signatures of subsurface objects.

Many students have difficulty getting beyond the “plug and chug” uses of equations to understand physical processes. Illustration of these equations using a spreadsheet allows students to see how changes in different variables affects the shape of curves on a graph, and how different variables interact. In more advanced classes, the solver function in a spreadsheet is useful for illustrating finite-difference numerical methods. Electronic presentation enhances interactivity and the quantitative understanding of these topics.