The Economist

A PARADOX of education is that presenting information in a way that looks easy to learn often has the opposite effect. Numerous studies have demonstrated that when people are forced to think hard about what they are shown they remember it better, so it is worth looking at ways this can be done. And a piece of research about to be published in Cognition, by Daniel Oppenheimer, a psychologist at Princeton University, and his colleagues, suggests a simple one: make the text conveying the information harder to read.
Dr Oppenheimer recruited 28 volunteers aged between 18 and 40 and asked them to learn, from written descriptions, about three “species” of extraterrestrial alien, each of which had seven features. This task was meant to be similar to learning about animal species in a biology lesson. It used aliens in place of actual species to be certain that the participants could not draw on prior knowledge.
Half of the volunteers were presented with the information in difficult-to-read fonts (12-point Comic Sans MS 75% greyscale and 12-point Bodoni MT 75% greyscale). The other half saw it in 16-point Arial pure-black font, which tests have shown is one of the easiest to read.