Ask the question before you teach

The polite start to a teaching session is a slide of learning outcomes. People read it. Nobody has to try. The point that had to land is still somewhere in the pile.

A sharper start is slightly rude: ask the question first, while the answer is still in the session you have not given.

What the evidence says

Psychologists call this pretesting, or prequestions. The consistent finding is that an unsuccessful attempt before study can make the later study more useful.

Richland, Kornell and Kao ran five experiments on a passage about vision. One group answered questions about ideas buried in the text, then read it. Another group had extra time with the same passage, and the important words were italic or bold so the pretest was not just a highlighter. Later tests favoured the group who had tried first. They analysed only items people had missed on the pretest, so a lucky first hit is not the explanation. The advantage was still there a week later. In the last experiment, seeing the questions and trying to memorise them, without answering, was weaker than actually guessing.

That is not a claim that a pretest beats every other use of a quiz. Pan and Sana put a test before a passage against a test after it, in five experiments with 1,573 people. The items were multiple choice, or a short written answer, with or without the correct option shown. The later check came after five minutes or after 48 hours. Both kinds of test beat having none. The pretest was at least as useful as the post-test, and in their combined look across the first four experiments it was ahead: a small-to-moderate edge on the questions that had been asked (d = 0.30), and a smaller one on questions that had not (d = 0.14).

A teaching room is longer than a lab passage. Toftness, Carpenter, Lauber and Mickes used real course lectures, just over 20 minutes, on signal detection theory and on autobiographical memory. After dropping a handful of people whose video failed or who already knew the material, 97 sat Experiment 1. The pretest group got 29 percent of those opening questions right, then 81 percent of the same items after the lecture. Overall they scored 76 percent on the final 20 questions, against 67 percent for people who just watched (d = 0.52). The gain was on the prequestioned items (d = 0.76). The other half of the lecture was not reliably better. Experiment 2, a 24-minute lecture, showed the same overall pattern (d = 0.44). How interesting people said the topic was did not change the result. On a two-minute film the same group had earlier seen a spillover to unasked facts. A real lecture did not reliably give you that.

If the opening questions are multiple choice, the wrong options can do extra work. Little and Bjork found that a pretest with competitive alternatives helped people learn related facts that had never been the question, more than a short-answer pretest or reading those facts up front. The advantage was still there two days later, and it was not because they spent longer on those sentences.

What to do in the session

You do not need a paper before the door opens. You need two or three questions on the points that would worry you if they were still missing at the end.

1. Ask them before the first teaching slide. A guess is allowed. Silence is a guess.
2. Do not spend the next ten minutes marking it. The session is the correction.
3. Teach to those points. If a pretest only aimed at one decision, do not treat the rest of the hour as covered.
4. Ask the same points again at the close, from memory. That is a different job: it tells you what survived the teaching.

A learning-outcomes slide is not this. Reading "by the end you will be able to…" is not an attempt. Pan and Sana's pretest still worked when the first try had no feedback. The attempt is the mechanism.

What this does not mean

It does not mean a cold pretest is a diagnosis of the room. People will be wrong. Richland's analyses were built on that.

It does not mean the rest of the lecture comes along for free. In a 20-minute course video, Toftness and colleagues found the gain on the items they had asked. Cover the other must-lands with their own questions, or with the close.

It does not replace the quiz after you have taught. Both beat no test. The opening question aims attention. The closing question is retrieval of something that has actually been presented.

It does not mean a list of implausible options is a pretest. Little and Bjork's extra benefit for related facts sat on competitive alternatives.

It does not install a procedure you have not demonstrated. These studies used passages, facts and lecture videos, not a skill that has to be done with the hands.

Sources

• Richland LE, Kornell N, Kao LS. The pretesting effect: do unsuccessful retrieval attempts enhance learning? Journal of Experimental Psychology: Applied. 2009;15(3):243-257.
• Pan SC, Sana F. Pretesting versus posttesting: comparing the pedagogical benefits of errorful generation and retrieval practice. Journal of Experimental Psychology: Applied. 2021;27(2):237-257.
• Toftness AR, Carpenter SK, Lauber S, Mickes L. The limited effects of prequestions on learning from authentic lecture videos. Journal of Applied Research in Memory and Cognition. 2018;7(3):370-378.
• Little JL, Bjork EL. Multiple-choice pretesting potentiates learning of related information. Memory & Cognition. 2016;44(7):1085-1101.
• Carpenter SK, Toftness AR. The effect of prequestions on learning from video presentations. Journal of Applied Research in Memory and Cognition. 2017;6(1):104-109.