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Decline in interest is an endemic problem at schools, especially in rich countries. This decline is most prevalent at middle school and for difficult subjects like mathematics and the sciences.
What could teachers do to increase interest at school?
An easy way is to make school fun by showing glossy images or by cracking jokes. Although these accompaniments to subject matter indeed raise interest among students, they have the decisive drawback that they decrease learning, especially for weak students. Let us look at the pertinent evidence.
The Dr. Fox-Effect
A first study was the demonstration of the Dr. Fox-effect (click here for a more detailed description). In the original study, a certain Dr. Myron Fox was introduced as an authority on Game Theory and gave a talk. The audience gave him highly favorable ratings as an effective speaker. In fact, Dr. Fox was an actor. All he knew about game theory he had read in a Scientific American article; many in the audience probably know more than on that theory than him. He cracked some jokes and gave an enthusiastic but academically incoherent 20-minute talk.
This finding has to be interpreted with a grain of salt. Later research showed that even if students rate a lecturer telling pseudo-academic gibberish high on effectiveness as a speaker, they were not fooled into believing that they had learned much. And rightly so: Where there is not much content, there is not much to learn. So the Dr. Fox effect is a prelude to seductive details that students like a lot even though they learn little.
Seductive Details
Old text- and workbooks for math and science education were texts with formulas and practice tasks printed on brownish paper. Modern books, by contrast, are glossy and include colorful pictures. While many of the pictures are graphs or illustrate a principle, some are purely decorative, such as a palm beach on a tropic island besides a math problem on interest rates when saving money for holidays. Such pictures render materials more interesting.
Most importantly, however, materials that do not directly illustrate the learning content are not only pleasant but also impair learning, especially for academically weak students. This is why such pictures have been called seductive details.
There are other kinds of seductive details. For example, mathematics teachers might tell anecdotes about the death of Évariste Galois in a duel, or about the poverty of Niels Henrik Abel. Many popular science books blend such anecdotes with scientific facts in order to appeal to the reader. Jokes in class or cartoons in textbooks are other kinds of seductive details.
Why do seductive details harm learning? Reading materials uses up attention which is a limited resource. When students attend to process a glossy picture or a hilarious joke, they lack the attention necessary to understand mathematical principles or grammar in a foreign language.
Why do seductive details harm weak students more than strong ones? One reason is that weak students might already have problems with attention. If seductive details detract the little attention they have to enjoy the pictures or understand the joke, they are lost when it comes to understanding subject matter. Students with better attention span suffer less from seductive details and can therefore learn despite being distracted.
In addition, strong students are more likely to understand a mathematical principle anyway. Hence, they need to pay less attention than a student who is weak. Even if the strong and the weak student have the same attention span and therefore do not differ how much information they could process, the student who understands mathematics or grammar easily can look at the irrelevant pictures without loss. Weak students, by contrast, would need all the attention they could muster to understand the subject matter. They cannot afford wasting this precious resource on pictures and jokes.
How to Do it Right?
Is there only a choice between learning well but suffer boredom and having exciting lessons without learning much? Not necessarily.
The crucial point with seductive details is that they only superficially connect to the materials at hand. Let us come back to the workbook page dedicated to calculation of interest rates illustrated with a glossy picture of a palm beach. Students who focus on the picture and dream of their next holiday are lost and will hardly learn when they have to start saving money if they ever want to visit that island.
By contrast, pictures that explain the text have been shown to improve student learning. For example, the physics of thunderstorm accompanied by illustrations of the electrical charges help students understand the principle underlying this event. However, even when the illustration matches the learning content, teachers or learners have to make the connection between picture and text in order to benefit from the combination of these two communication channels.
The same applies to anecdotes and jokes. They have to illustrate the content, not to detract from it. Actually the same kind of anecdote may detract from the essentials or help understand them. For example, the fact that the mathematician Niels Henrik Abel lived in poverty does not help understand his major proof. The fact that writer Knut Hamsun lived in poverty helps understand his literary work and maybe even his later political aberrations.
The goal should be, as philosopher Roger Scruton proposed, that “true teachers do not provide knowledge as a benefit to their pupils; they treat their pupils as a benefit to knowledge.” This means that as teachers and textbook authors, we do not try to make things interesting for the sake of entertaining our students but for the sake of transmitting the treasures of knowledge of our culture to the next generation.
The take-home message is that teachers and textbook authors should not try to pep up learning materials with seductive pictures, anecdotes or jokes that detract attention necessary to understand and remember the materials. Accompaniments that make stuff interesting have to illustrate content in a way that it can be integrated in memory.
Seductive details are discussed in:
Reber, R. (2016). Critical feeling. How to feelings strategically. Cambridge: Cambridge University Press.
