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Carl Wieman, Why Not Try a Scientific Approach to Science Education 105Given that there are thousands of traditional science lectures being givenevery day, these results are quite disturbing. Do these findings make sense?Could this meager transfer of information in lectures be a generic problem?These results do indeed make a lot of sense and probably are generic,based on one of the most well-established—yet widely ignored—results ofcognitive science: the extremely limited capacity of the short-term workingmemory. The research tells us that the human brain can hold a maximum ofabout seven different items in its short-term working memory and can processno more than about four ideas at once. Exactly what an “item” means whentranslated from the cognitive science lab into the classroom is a bit fuzzy. Butthe number of new items that students are expected to remember and processin the typical hour-long science lecture is vastly greater. So we should not besurprised to find that students are able to take away only a small fraction ofwhat is presented to them in that format.Understanding Basic ConceptsWe physicists believe that one of the great strengths of physics is thatit has a few fundamental concepts that can be applied very widely. Thishas inspired physics-education researchers to study how well students areactually learning the basic concepts in their physics courses, particularly atthe introductory level.These researchers have created some good assessment tools for measuringconceptual understanding. Probably the oldest and most widely used of theseis the Force Concepts Inventory (FCI) (Hestenes, Wells, & Swackhammer,1992). This instrument tests students’ mastery of the basic concepts of force