Have you ever felt you had completely mastered a topic… until someone asked you to explain it? Finding the right words, organising your ideas, answering an unexpected question: passing on knowledge is often harder than you think. It is also one of the best ways to learn. Why does teaching someone else help us understand and remember better?
Understanding and being able to explain: two different skills
Imagine a student who has just finished a biology chapter. They followed the lecturer’s explanations, reread their course notes and understood the examples. They feel they have a good grasp of the material.
A few days later, a classmate asks them to explain a mechanism from that chapter. The student starts, then hesitates. They can’t remember certain terms, struggle to connect two ideas and realise they cannot justify one step of the reasoning. Yet when they reread their notes, everything seems perfectly logical.
This situation shows an essential distinction: recognising information and being able to recall it on your own are not the same thing.
When you read a text or listen to an explanation, you benefit from a structure that has already been built: the ideas come in a certain order, the links are spelled out, the examples guide you. Explaining an idea yourself forces you to rebuild that structure: find the relevant information, organise it and put it into your own words. It is precisely this effort that makes the exercise so useful.
Explaining forces you to organise your knowledge
When you learn new material, the information is not always neatly organised in your mind. You know a few definitions, a few formulas and a series of examples, without really understanding how they fit together. Explaining a subject to someone pushes you to make those connections.
Take a pupil who has to explain the French Revolution to their little brother. They could list a few dates and events. But to be understood, they will probably have to answer more fundamental questions:
- why did the Revolution start?
- what tensions ran through French society?
- how did the events unfold?
So they have to go beyond memorising facts and build a coherent line of reasoning. Researchers in the science of learning call this elaboration: enriching your knowledge by making connections between pieces of information. The more you link ideas together, the more routes you have to understand them and find them again later.
This is one of the reasons why explaining a subject is often more instructive than rereading it several times. Experiments have also shown that students who expect to teach a subject learn it better than those who only expect a test, and that actually explaining it strengthens this effect further.
The power of simple words
Explaining a complex idea to someone who doesn’t know it forces you to simplify. Not by removing what matters, but by looking for a more accessible way to present it.
A physics student explaining air pressure to a child cannot just recite a definition. They will have to use concrete examples, comparisons or experiments that are easy to picture. To do so, they need to identify what really lies at the heart of the concept.
This approach is close to the Feynman technique, named after the physicist Richard Feynman, known for his ability to make complex scientific concepts accessible. In its popular version, it consists of choosing a topic, explaining it simply, spotting the difficult parts, then going back to the material to improve your explanation.
It is not a magic recipe, and the method has not been scientifically validated step by step under that name. But it relies on well studied learning mechanisms, in particular recalling knowledge from memory and rephrasing it. And it rests on a very useful idea: if you cannot explain an idea clearly, your understanding is often still incomplete.
Explaining to discover what you haven’t mastered yet
One of the great advantages of explaining is that it brings gaps to light.
When you reread a lesson, it is easy to feel you know everything: the information is familiar, the explanations seem obvious, you recognise the ideas. This familiarity can create an illusion of mastery. But as soon as you have to explain the material without your notes, difficulties appear: a forgotten step, a definition you don’t really understand, a result you can’t justify.
These moments of hesitation are valuable. They help you tell apart what you really know from what you thought you knew. This is called metacognition: the ability to think about what you know, what you understand and how you learn.
Explaining a subject thus becomes a form of self-assessment. Rather than discovering your gaps on exam day, you spot them while revising, when there is still time to fix them.
Other people’s questions make you think differently
Talking to another person has a further advantage: they can ask questions you hadn’t thought of.
A child who asks “Why?” several times in a row quickly pushes an adult to dig deeper into a topic they thought they had mastered. Likewise, a classmate who doesn’t understand a step in a mathematical argument can lead us to look for another proof or go back to a basic principle. You then have to adapt your explanation, consider other points of view, and sometimes admit that you don’t know the answer yet.
That is the whole point of peer learning, when pupils or students work together and explain ideas to each other. With one caveat: a wrong explanation can also pass on a wrong understanding. So it remains important to check information against the course, the textbook or with a teacher.
Teaching to learn, at any age
This approach can be adapted to almost any level:
- In primary school: a child can explain to their parents how they solved a maths problem. Rather than just checking whether the answer is right, you can ask them to talk you through the steps of their reasoning.
- In secondary school: two pupils can revise together by taking turns explaining chapters to each other. The one explaining consolidates their knowledge; the one listening gets a different presentation from the teacher’s.
- In higher education: students can organise small sessions where each person presents part of the material to the others. This is particularly useful for courses that require understanding mechanisms, reasoning or links between several concepts.
- At work: explaining a procedure to a new colleague also helps you master it better.
The principle stays the same: turning knowledge you have received into an explanation you can produce yourself.
Do you really need someone to explain things to?
Good news: no. You can practise explaining an idea out loud, as if you were talking to someone who doesn’t know the subject. Some people rebuild a line of reasoning on a blank sheet of paper, others record themselves explaining a chapter, or imagine having to present it to a twelve year old. The key is not simply to read your notes.
Here is an easy method to apply:
- Choose a precise idea. For example photosynthesis, a grammar rule or an economic concept.
- Close your book. Explain the idea in your own words, without looking at the original explanations.
- Imagine a beginner’s questions. Why does it work this way? What is it for? Can you give an example?
- Spot your hesitations. Note what you have forgotten or can’t justify.
- Go back to your notes. Fill in your understanding, then start the explanation again.
A few minutes at the end of a study session are enough. It is particularly useful for checking that you really master an idea before moving on to the next chapter, and it is a good complement to effective note-taking .
Explaining does not replace practice
That does not make it a universal solution. Being able to explain a maths method does not guarantee you can apply it in every exercise. Explaining the grammar rules of a language is not enough to speak it fluently. Some skills require regular practice, automatic reflexes and a variety of situations.
Explaining therefore complements exercises, practical situations and other revision methods. It is especially useful for deepening understanding, structuring knowledge and checking what you have remembered.
That is also why good support is not just about giving the student explanations. It is just as useful to ask them to explain in turn what they have just understood. In My Sherpa’s private tutoring , this helps coaches spot remaining difficulties, check that ideas have been understood and help the student become independent. Because the goal is not only to understand an explanation when it is given, but to be able to use your knowledge on your own, in a new exercise or in an exam.
What if the best way to check what you know were to explain it?
We naturally associate learning with receiving knowledge: listening to a teacher, reading a textbook, watching a video. But learning also means being able to retrieve, organise and use that knowledge on your own. Explaining an idea to someone forces you to do exactly that: choose what matters, build a line of reasoning, find the right words, and sometimes answer unexpected questions.
The exercise may reveal gaps, and that is exactly what makes it worthwhile. Next time you feel you have completely mastered a chapter, try explaining it to someone who doesn’t know it. You may discover there are still points to work on. Or, on the contrary, that you can make simple what seemed complicated to you a few days earlier. Either way, you will probably have learned something.
Getting support
Does your child feel they know their subject, yet their results don’t follow? At My Sherpa, an educational advisor first takes stock with you, then chooses a coach who checks with your child what has really been learned and helps them build effective study skills . Lessons take place at home anywhere in Belgium, or online.
