The Science Storm: Which Side of the Spectrum?

2. The Science Storm: Which Side of the Spectrum? My dad taught life sciences to junior high students and college students for more than 30 years. He also taught science in the backyard, from the front seat of his car, and at the family dinner table. His insatiable curiosity and boundless enthusiasm for any scientific subject propelled his need to teach his students and his children in whatever method they could understand… Dad was an endless well of both facts and unanswered questions, and that combination of the ability to explain anything and the confidence to let the student figure something out has been my benchmark for good science teachers throughout my life. Good science teachers at every level know instinctively that they have to modify their methods to adapt to the child, and that present students with a combination of instruction and the experience of finding something out for themselves. Some rely more heavily on lecture and instruction; some feel strongly that exploration and hands-on discovery are the way to go. New research from Carnegie Mellon University questions whether one particular method of teaching science is better than another. The ensuing debate has provoked a tempest in a Petri dish. David Klahr's research showed that children (second to fifth grade) who learned by direct instruction how to best design experiments by limiting the number of variables not only retained the information when tested several months later, they were potentially better able to design experiments in other disciplines. Too much go-with-the-flow, Klahr suggests, without the structured support of instruction, does not effectively teach some concepts. The Control Variables Strategy, according to findings from Klahr's research, is "the skill that allows scientists to design unconfounded experiments and to draw valid conclusions from experimental outcomes." Good experiment design is a skill essential to all forms of scientific inquiry and one that, according to Klahr, is not effectively learned through exploration. Direct instruction is necessary to the teaching of this concept. Yet when dealing with misconceptions, direct learning sometimes has little or no effect in overcoming the misconception. "When you directly tell the learner something that contradicts their misconception, it has no impact," says Gerry Wheeler, executive Director of the NSTA. "If you try to do straight explanatory when talking density with a fifth grader, odds are they won't get the concept. If you don't let them explore, they don't get it." But if you don't explain the concept and the formula (mass divided by volume, and the fact that mass isn't weight) then all their exploring may or may not lead to comprehension, especially when dealing with students below sixth grade. "Some topics are rich in misconceptions," Wheeler says. A good science teacher has to again range up and down that spectrum of techniques, using both direct instruction and exploratory learning to get the concept across.