A short while back PNAS published a meta-analysis of studies by Freeman et al comparing traditional lectures with those that include more ‘active’ activities. In an accompanying news and views, Carl Wieman defined those active methods as follows: ‘In active learning methods, students are spending a significant fraction of the class time on activities that require them to be actively processing and applying information in a variety of ways, such as answering questions using electronic clickers, completing worksheet exercises, and discussing and solving problems with fellow students.‘ The magnitude of the effect was large, with some measures showing an effect size of 0.47. In a letter just published, Hora argues that it is hard to define exactly what traditional lectures are, and that there may be much heterogeneity in this group. In his words ‘the jury is still out on lecturing (his argument is more nuanced that this, so read his words).
I have sympathies on all sides. Lectures are not a natural kind, and the delivery, format and style will, I suspect, interact with content and the target group. To some extent, the question, ‘ Do lectures work?’ is a bit like asking ‘Do drugs work?’ Having said all of the that, the weight of evidence seems clearly be in favour of more active methods. There are however other things to think about.
Changing how you do things in a traditional course is not like swapping one pill for another. Nor are studies based on single courses necessarily a good guide to what happens when you implement widespread change. Most importantly, much as though I think you can improve learning using more active methods in lectures, we need to look hard at why we rely on lectures to such an extent, and how we can phase many or most of them out (at least in medicine). We also need to work out when we should use them. Drugs have both benefits and side effects too (or at least unintended actions); some of the latter are occasionally useful. The art, is in matching the type of drug, to the type of patient, at the right time.
To weigh the evidence, Freeman and a group of colleagues analyzed 225 studies of undergraduate STEM teaching methods. The meta-analysis, published online today in theProceedings of the National Academy of Sciences, concluded that teaching approaches that turned students into active participants rather than passive listeners reduced failure rates and boosted scores on exams by almost one-half a standard deviation. “The change in the failure rates is whopping,” Freeman says. And the exam improvement—about 6%—could, for example, “bump [a student’s] grades from a B– to a B.”
“This is a really important article—the impression I get is that it’s almost unethical to be lecturing if you have this data,” says Eric Mazur, a physicist at Harvard University who has campaigned against stale lecturing techniques for 27 years and was not involved in the work. “It’s good to see such a cohesive picture emerge from their meta-analysis—an abundance of proof that lecturing is outmoded, outdated, and inefficient.”