01 February, 2009

Teaching Tips for Science Labs

How to move beyond the `cookbook' method and encourage `discovery learning'.

Even in the most structured labs there are ways to help your students learn through inquiry by helping them exercise their investigative skills. Here are a few tips you may want to consider when designing or conducting your next science lab:

• Instead of assigning the topic of the experiment, such as "the effect of pH on the reproductive rate of yeast," phrase the topic as a question: "Does the pH affect the reproduction rate of yeast?"

• When stating the purpose of the experiment, avoid presuppositions or foregone conclusions, such as "to show that yeast reproduce better in acidic pH". Don't give an answer, have the students investigate for one: "The purpose is to test the effect of various pH levels (if any) on the reproduction rate of yeast."

• Try to ask questions that are general enough so that students are not "guided" to a particular result or variable. For example, ask "What were your findings?" instead of "In which test tube did you find the largest amount of yeast?" Or ask "What was the role of each of your test tubes?" rather than: "Why did you mark test tube number 9 as control?"

• Instead of asking students for a summary statement ("Explain the presence of acidic pH in the regular environment of yeast"), ask students to design a new experiment or to extend their experiment by using the same equipment in the lab ("Design an experiment to test the effect of another variable on the reproduction rate of yeast").

• Instead of providing students with prepared graphs or charts and then asking them to enter their data, such as "Enter your data in the graph provided by the manual," ask students to chart their own results: "Draw a graph to show the relationship between the reproduction rate of yeast and the pH level."

Such tips invite students to exercise their own powers of critical thinking, problem solving, creativity, analysis, synthesis, or data evaluation in even the most structured experiments. In the end, students may walk out of your laboratory course with greater confidence, responsibility, and a greater understanding of the risks, rewards, and uncertainties associated with scientific inquiry.

(Adapted from: "The Laboratory," Guidelines for Improvement of Instruction in Higher Education - University of Virginia.)