Helping kids learn math and science:

Why kids benefit when they teach others

© 2009 -2013 Gwen Dewar, Ph.D., all rights reserved

Want to help your kids learn math and science?

Ask them explain—or, better yet—teach what they are learning in their own words.

This simple tactic can help kids master new material.

You’ve probably experienced it yourself. People become better problem-solvers when they are asked to explain how or why a solution is correct.

Explaining is an especially effective learning aid when people try to teach another person. But it’s also helpful if they merely explain their reasoning to themselves.

For instance, a study of novice chess players found that individuals who were told to explain a computer’s moves became better players than people who simply observed the computer’s moves (de Bruin et al 2006).

And here’s another example: In a study of 9th graders, students were presented with a new geometry theorem. Some students were trained to “self-explain” as they studied. Other students were allowed to study in their usual ways.

When the teens were tested on their overall comprehension, the “self-explainers” had the advantage. They were better able to solve new problems that were superficially different, yet conceptually connected with the assigned theorem (Wong et al 2002).

Explaining appears to help younger kids, too.

In one study, Bethany Rittle-Johnson and her colleagues (2008) gave 5-year olds some pattern-detection problems to solve.

Each problem consisted of a sequence of 6 plastic bugs—e.g.,

And kids were asked what comes next (e.g., a red spider).

After each child gave his answer, the experimenter told him the correct answer. Then the experimenter asked the child to explain the correct answer.

Compared to kids who were asked merely to repeat the right answer out loud, the “explainers” went on to become better problem solvers. When they were asked to solve a new set of pattern-detection problems, they were more likely to get the right solutions.

Why does self-explanation help kids learn math and science?

Perhaps it forces them to wrestle with the underlying concepts, making them discover connections we might otherwise overlook.

For instance, recent work by Cristine Legare (2010; 2012) suggests that preschoolers are especially likely to attempt explanations when they encounter new data that don't jibe with their prior beliefs.

Inconsistent outcomes prompt kids to think about possible, hidden causes and unseen mechanisms. The explanations they generate then inspire them to actively test their ideas.

In one recent experiment, Legare found that children as young as two years spent more time exploring a toy -- and explored it more systematically -- after they had offered explanations about how it worked (Legare et al 2012).

So explaining may be valuable because it makes us aware of what we don't yet understand. If so, then we might expect self-explanation to be less helpful when kids are already well-informed about the concepts. And that seems to be the case.

Rittle-Johnson and colleague Percival Matthews presented 2nd through 5th graders with algebra problems, teaching some kids concept-driven lessons and other kids lessons that merely explained a procedure for solving the problems (Matthews and Rittle-Johnson 2008).

When given problems to solve on their own, kids showed no differences in their grasp of the procedure. The kids who’d received concept-driven lessons were just as competent as the kids who’d received procedural instruction.

But there was a difference when it came to understanding the “big picture.” Kids who received concept-driven instruction demonstrated more conceptual knowledge.

So it seems that concept-based instruction is more efficient than procedural instruction.

And self-explanations? They had no effect. Matthews and Rittle-Johnson conclude that quality, concept-driven instruction can make self-explanation unnecessary.

But if my own school experiences are any guide, kids don’t always get high-quality, concept-driven instruction. In these situations, kids might really help themselves by attempting to explain their solutions to another person.

Turning kids into teachers

We’ve seen that self-explanation helps kids learn math and other material. Does it matter if there is an audience? Probably. In the bug experiment for 5 year-olds, Rittle-Johnson and colleagues found that kids performed best when they were asked to explain to their mothers (as opposed to themselves).

And other studies have shown that active teaching makes a difference.

In one study, college students were given a reading passage to study.

• Some were told they would be tested on it later

• Some were told they would have to teach others about it (but did not end up doing so)

• Some were told they would have to teach and they did go on to teach it

Who learned the material the best? When tested on their comprehension, the students who’d prepared to teach it performed better than those who merely studied it. And the students who’d prepared AND actually taught it performed the best of all (Annis 1983).

Can we apply these results to kids? I think so. Brown and Kane performed a clever experiment on 3-year olds. First, they asked kids to solve a problem from a story: A man needed to stack tires on a shelf too high for him to reach.

If kids couldn’t solve it, researchers explained the answer: He should stack up some of the tires to make a stool.

Then, kids were presented with a second analogous, second story: A farmer who needed to stack hay bales on a tall tractor. Could they solve this problem themselves?

Some kids were told to simply recount the story. Others were told to teach a puppet the solution.

The kids who were asked to teach were twice as likely to solve the problem on their own (Brown and Kane 1988)

More information

For a related look at self-explanation and learning, see my article about the role that gestures play in helping kids learn math, science, and the meaning of new words.

For more tips to help kids learn math and science, see my article "Science for kids: How to raise a science-minded child."


References: How self-explanations and teaching tasks can help kids learn math and science

Annis LF. 1983. The processes and effects of peer tutoring. Human learning: Journal of Practice and Research Applications 2(1): 39-47.

Benware CA and Deci EL. 1984. Quality of learning with an active versus passive motivational set. American Educational Research Journal 21(4): 755-65.

Brown AL and Kane MJ. 1988. Preschool children can learn to transfer: Learning to learn and learning from example. Cognitive Psychology 20: 493-523.

de Bruin ABH, Rikers RMJP, and Schmidt HG. 2007. The Effect of Self-Explanation and Prediction on the Development of Principled Understanding of Chess in Novices. Contemporary Educational Psychology 32(2):188-205.

Legare C. 2012. Exploring explanation: explaining inconsistent evidence informs exploratory, hypothesis-testing behavior in young children. Child Dev. 83(1):173-85.

Legare CH, Gelman SA, and Wellman HM. 2010. Inconsistency with prior knowledge triggers children's causal explanatory reasoning. Child Dev. 81(3):929-44.

Matthews P and Rittle-Johnson B. 2009. In pursuit of knowledge: Comparing self-explanations, concepts, and procedures as pedagogical tools J Exp Child Psychol. 104(1):1-21.

Rittle-Johnson B, Saylor M, Swygert KE. 2008. Learning from explaining: does it matter if mom is listening? J Exp Child Psychol. 100(3):215-24.

Wong RM, Lawson MJ, and Keeves J. 2002. The effects of self-explanation training on students' problem solving in high-school mathematics Learning and Instruction 12(2): 233-262