Why bold isn't always best for learning

21st March 2014 at 00:00
For teaching materials, a clear typeface is best, right? Not necessarily. It seems that hard-to-read fonts may help students

Read this word: heavy. Now try it again: heavy. You should have found the first representation of the word easier to read and understand, according to a 1989 study by two British psychologists. Why? Because reaction times to words are slower if the perceptual qualities of the font are inconsistent with the meaning, as in the rendering of the second word.

Let's try another. Read this: heavy. Now this: heavy.

Which was easier on the eye? You should have found the second example more legible. As a result, there's a stronger chance that as a teacher you would intuitively opt to use the latter typeface - Arial - or a similar font, on worksheets, handouts and revision notes for your students. This is because you want the information to be as easy to read as possible, so that it assists their learning. However, it turns out that decision may, in fact, have the opposite effect.

A study by three US academics published in 2010 found that using the heavier-set Haettenschweiler typeface (the first example) would actually be more beneficial. Because it's harder to read, students would need to spend more time and energy processing the words. In doing so, the theory goes, they would absorb more information.

Seeing clearly.or not

Suddenly, opting for a font simply because you like its style seems a little haphazard. As these studies underline, there is compelling evidence to suggest that teachers should be giving careful consideration to the fonts they use. Just opting for the seemingly ubiquitous Comic Sans could have a big, and negative, impact on learning.

So which typefaces should teachers be using? Which should they steer well clear of? What other typographic tricks can they employ to aid learning?

It is difficult to find a clear answer. This is not from a lack of research: the number of studies on the impact of typefaces on learning has increased considerably in the past few years. Simon Garfield, author of Just My Type: a book about fonts, says this is owing to the enormous choice of typefaces now available to teachers on their computers. However, the research does not seem be getting much attention.

"In the education system, if you go back 25 years, teachers would have had a choice of just a few typefaces that, over decades or maybe hundreds of years, had proved to have worked," Garfield says. "They would have been very dull but they would have been predictable and trustworthy. However, thanks to computers, we know much more about typefaces today. We're now gods of our type and we tend to play around with typefaces far more often to find out what works."

Garfield believes that people generally base their font choices on this experimentation rather than the research, and that choice is usually determined by individual aesthetic preferences rather than other criteria.

Mary Dyson, associate professor in the typography and graphic communication department at the University of Reading, agrees. She says it is unlikely that teachers would consciously choose a font that is difficult to read or give the topic much thought beyond readability. "I suspect the choice of font by the teacher is a personal preference," Dyson says. "What they have used before and what they think works OK."

But according to Dyson, teachers need to give more thought not just to font choice but how the font is presented. "The way in which the teacher uses the font - interlinear spacing, type size, layout, line length, etc - may all indicate their sensitivity to the importance of information design, which is likely to have a greater impact on learning than the font alone," she says.

These are the sorts of insights available from the academic studies that teachers may never have considered. So what else does the research say?

Well, it offers a series of slightly mixed messages. Work undertaken by Dyson's colleague Sue Walker advocates clarity. From 1999 to 2005, Walker led a study on how typography affects children's reading. Its many insights included the fact that children are more sensitive to differences in letter spacing than to word spacing: the students in the study found that letters tightly set together made the type look darker, thicker or smaller and therefore more difficult to read.

Walker also helped to develop a screen typeface called Fabula, with characteristics designed to aid the comprehension of six- and seven-year-olds. So, for example, Fabula makes clear distinctions between characters that are often easily confused, such as "a" and "o", or a lower case "l", capital "I" and the figure "1".

Some academics, however, question whether readability and learning can be lumped together. Indeed, the trio behind the 2010 US report argue that using what are termed "disfluent" fonts in the classroom could have significant benefits for students' understanding.

"Fonts that are slightly difficult to read signal to the brain that it is dealing with more difficult information and therefore requires higher-level processing, in the same way that the math problem 44 x 29 signals more difficulty than 2 x 8," explains one of the report's co-authors, Connor Diemand-Yauman of Princeton University. "Even though the material isn't more difficult when written with disfluent fonts, our brains in many ways respond as if it is, much to our benefit."

His Princeton collaborator Daniel Oppenheimer expands on the point. "People often confuse the source of difficulty," he says. "So when you use a slightly more difficult-to-read font, people can confuse that with how difficult the material is to process. This can lead them to attend more deeply to the material, process it more thoroughly and otherwise expend more mental effort. This means that slightly more complex fonts lead people to do better on tasks that require deep thought and also can help people to better learn material."

He adds that in studies which he has run - both in the lab and in classroom environments - students perform significantly better on memory tasks when they are exposed to the materials in a font that is harder to read.

The sweet spot

So how can teachers use these findings to aid their students' learning? Diemand-Yauman recommends rotating between the disfluent fonts that were used in his research - Haettenschweiler, italicised Comic Sans and Monotype Corsiva - and steering clear of the popular, more "fluent" fonts such as Arial and Times New Roman.

This obviously contradicts the other pool of research, which stresses the importance of clarity. But Diemand-Yauman concedes that different people and age groups will respond to disfluent fonts in a variety of ways. And he argues that there is a middle way between the disparate findings which will be helpful for teachers. "The rule of thumb for any group is to make the font slightly more difficult to read without becoming overbearing or negatively affecting their willingness to engage with the content," he advises.

Where that sweet spot sits for particular groups of students will be a matter of trial and error. And it may be a process that teachers wish to use not just for the resources they personally produce for students, but also for the wide variety of texts, guides and editions they recommend or distribute to their classes.

For the studies all agree that font choice and layout have a clear impact when it comes to learning - whether they have the effect of making texts more difficult or easier to read - so, unfortunately, simply relying on the one you think looks the nicest is no longer a sensible option.

What else?

Source material: we reveal what happened when students chose their favourite fonts.


Print works: designing a typeface to help dyslexic students.


Font of all knowledge: the story of typefaces.



Lewis, C and Walker, P (1989) "Typographic influences on reading", British Journal of Psychology, 80: 241-257.

Diemand-Yauman, C, Oppenheimer, DM and Vaughan, EB (2010) "Fortune favours the bold (and the italicised): effects of disfluency on educational outcomes", Cognition.


Typographic Design for Children Project.


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