Learning by teaching: why explaining to others helps you learn

Would explaining a lesson to someone else help you understand it better? Research suggests it can. The useful work comes from preparing an explanation, working out why ideas connect and checking what you got wrong. At home, the aim is to use explanation to understand a lesson rather than simply recite it.

Different ways of learning through explanation

Self-explanation means working out how a process works or why ideas connect. You can do it alone. Teaching adds an audience. Expecting to teach changes the task before you begin explaining. Each activity needs its own evidence, even though they are related. Self-explanation involves making sense of a passage, beyond simply reading it aloud.

The term protégé effect has a specific research history. In a 2009 paper, Catherine Chase and colleagues studied Betty’s Brain, a computer environment in which children teach a simulated learner. Across two studies, students made greater efforts when learning for that learner than for themselves. The finding was about effort in this particular setting, so its wider relevance to learning remains uncertain.

What Chi and colleagues found

In Michelene Chi and colleagues’ 1994 study, 14 eighth-graders were prompted to explain after each line of a passage about the human circulatory system. Another 10 students read the passage twice without those prompts. The prompted group made greater gains between the pretest and posttest.

This small study tested self-explanation using a particular biology passage, rather than teaching another person. For families, the useful part is the task: asking learners to make sense of what they read. Any effect on school marks remains unknown.

Preparing to teach, then actually teaching

Logan Fiorella and Richard Mayer’s published review describes their 2013 and 2014 experiments with college students learning the Doppler effect. Some students studied for a test, some expected to teach, and some also delivered a short video-recorded lesson.

The authors reported that preparation alone helped on an immediate comprehension test. After a one-week delay, benefits appeared only for students who had both prepared and taught. In these experiments, students benefited without a live listener. Whether preparation alone has lasting benefits in other settings remains an open question.

At home, try deciding before you study that you will explain the material afterwards. That gives your preparation a purpose, unlike an unexpected request to teach. This adapts the research; the college experiments did not test the same routine in Indian homes.

How large are the benefits?

Kiran Bisra and colleagues’ 2018 meta-analysis brought together 69 effect sizes from 64 research reports on prompted self-explanation. Its overall estimate was Hedges’ g = 0.55. This measures the average difference in learning outcomes between groups on a standardised scale, rather than a 55 per cent improvement in marks. The estimate applies to prompted self-explanation, rather than learning by teaching as a whole.

Kobayashi’s 2024 meta-analysis of 39 studies compared teaching after study with studying without an expectation of teaching. The pooled estimate was g = 0.27, with a 95 per cent confidence interval of 0.15 to 0.39. Preparation mattered: the estimate with prior teaching expectancy was g = 0.48, with an interval of 0.34 to 0.63. Without that expectancy, it was g = -0.02, with an interval of -0.14 to 0.11, and did not differ significantly from zero.

The same paper separately analysed 14 studies comparing preparing and then teaching with preparing alone. The additional benefit of teaching was g = 0.38, with a 95 per cent confidence interval of 0.17 to 0.60. That comparison favoured teaching after preparation. Read these estimates separately: each describes a different comparison. They are research averages, so an individual learner’s gain may differ.

Is the benefit simply remembering?

Retrieving material from memory may contribute. In a 2018 experiment, Aloysius Wei Lun Koh, Sze Chi Lee and Stephen Wee Hun Lim compared teaching without notes, teaching with notes, retrieval practice without teaching, and a control arithmetic task. On a comprehension test one week later, the teaching-without-notes and retrieval groups outperformed the teaching-with-notes and control groups.

That supports trying an explanation from memory before checking the source. The findings leave open whether teaching beats retrieval practice and how notes affect learning in other settings. Kobayashi’s 2022 review found mixed evidence when comparing explaining to others with recalling. It also noted a problem with some comparisons: reading a supplied teaching script can remove both recall and the work of creating an explanation. How the benefit arises remains unsettled.

When explanation becomes a recital

Rod Roscoe and Michelene Chi’s 2007 review warns that peer tutors often pass on existing knowledge rather than deepen their understanding. Explaining and questioning can help when learners check their understanding, connect new knowledge with what they already know, and develop ideas. Look for this work, rather than the length or confidence of a speech.

Fiorella’s 2023 theoretical review also identifies enough background knowledge and guidance as conditions for effective generative learning. Connecting new material with what you already know may explain the benefit. Learners need instruction before they can teach entirely unfamiliar material.

A routine to try at home

These steps bring together suggestions from the research for use at home. Researchers have not tested them as a single programme.

1. Begin with a lesson or worked example you can make sense of. Decide before studying that you will explain it afterwards.
2. Try explaining from memory. Focus on why the steps work and how the ideas connect, then check anything you cannot account for.
3. Invite a parent or sibling to ask why a step works, how two ideas connect, or what would change if a condition changed. These suggested prompts adapt the US Institute of Education Sciences recommendation to ask and answer explanatory questions. The exact wording has not been tested.
4. Reopen the textbook or worked solution. Look for an omission or incorrect step and explain the corrected version. Fiorella’s review describes using an expert representation and feedback to identify and repair errors.
5. Return to the material after a delay and try explaining or recalling it again. The Institute’s guide recommends delayed review. These sources give no ideal daily time for this combined routine.

What to aim for

Use explanation to work through reasons, check accuracy and return to what needs attention. If you are listening, ask how ideas connect rather than for a word-for-word account. If you study alone, you can use self-explanation. Keep practising after a successful explanation, which alone cannot show that you will remember the material permanently.

For guided independent learning beyond the syllabus, Learnacy Mentorship serves learners in Grades 8 to 12 and undergraduates through an ongoing, primarily online interdisciplinary mentorship. Its programme page describes mentor sessions and the learner’s own project work, with the journey designed around the individual.