Turning the tables to help kids learn math and science:

Why children benefit when we ask them to explain

© 2009 -2015 Gwen Dewar, Ph.D., all rights reserved

Want to help your kids learn math and science? Ask them to explain what they are learning in their own words.

You've might have noticed it yourself: We're more likely to really "get" a concept if we go to the trouble of explaining what we think.

For instance, novice chess players appear to hone their skills faster when they make explaining an explicit part of their training process. In one experiment, people asked to watch and explain a computer’s moves became better players than did people who simply observed the computer’s moves (de Bruin et al 2006).

Similarly, the act of explanation may help students may improve their understanding of mathematics -- even if nobody else is listening.

When researchers asked 9th graders to study for a geometry test by "self-explaining," these teens earned higher scores. Compared with students who studied in other ways, the "self-explainers" were better able to solve new problems that conceptually connected with the subject matter (Wong et al 2002).

But some of the most interesting research concerns much younger children. In one study of 5-year-olds, Bethany Rittle-Johnson and her colleagues (2008) gave kids some pattern-detection problems to solve.

Each problem consisted of a sequence of 6 plastic bugs like this:

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

After children answered, they were told the official solutions. Then they were asked to explain why the official answers were correct. The researchers put another group of kids through the same procedure, but without asking them to explain. Which group developed better pattern-detection abilities? When given new puzzles to solve, the "explainers" performed better.

Why does self-explanation help kids learn?

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

That's the contention of Cristine Legare and her colleagues.

They believe 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 hypotheses (Legare et al 2010; 2012).

Intriguing studies support this idea. For instance, Legare's team observed that 2-year-olds spent more time exploring a new toy after offering explanations about it. The toddlers were also more systematic in their investigations (Legare et al 2012).

And other experiments suggest that asking children to explain makes them focus on causation. When researchers have asked preschoolers to explain how a new device works, these children were subsequently more likely remember the unseen, causal properties of the device (Walker et al 2014; Legare and Lombrozo 2014).

So explaining may be valuable because it makes us aware of what we don't yet understand. If that's true, 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. When researchers provided school-aged children with high-quality, concept-driven instruction in mathematics, kids received no added benefits from self-explanation (Rittle-Johnson 2008).

Transforming children into teachers

We’ve seen that kids benefit from trying to explain. Does it matter if there is an audience? Probably. In the bug experiment for 5-year-olds, Rittle-Johnson and colleagues found that self-talk helped kids learn. But kids made even bigger gains when they explained their ideas to their mothers.

And there's good reason to think that playing the role of teacher can boost learning.

In an experiment on college undergraduates, students were given a passage to read and randomly assigned to one of three conditions:

  • Some students were told they would be tested on the material later
  • Some students were told they would have to teach a lesson about it (but did not end up doing so)
  • Some students were told they would have to teach and they did go on to teach it

Who learned the material the best? On a reading comprehension test, students who had been told they would teach got higher scores than other students did. And the students who performed best were the ones who had actually delivered a lesson (Annis 1983).

Of course, we can't assume that kids would benefit in the same way that college students do. But a clever experimental study by Brown and Kane (1988) offers intriguing hints than even 3-year-olds get a boost from trying to teach.

The study worked like this. Kids were given a chance to try to solve a problem encountered by a character from a story--a man who couldn't reach a high shelf.

If the kids were stumped, the researchers gave them the solution: There were some spare tires nearby. Stack the tires to make a stool.

Afterwards, kids were presented with a second, analogous story about a farmer who needed to stack hay bales on a tall tractor.

Could the children solve this problem by themselves? It depended on what happened  next. Some kids were told to simply recount the story before answering. Others were told to teach a puppet the solution. And that simple difference had a big impact. The kids who were asked to teach were twice as likely to solve the problem on their own.

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 information about science education, visit my page,  "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.

DeCaro MS, Rittle-Johnson B. 2012. Exploring mathematics problems prepares children to learn from instruction. J Exp Child Psychol. 113(4):552-68.

Legare CH and Lombrozo T. 2014. Selective effects of explanation on learning during early childhood. J Exp Child Psychol. 126:198-212.

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.

Walker CM, Lombrozo T, Legare CH, and Gopnik A. 2014. Explaining prompts children to privilege inductively rich properties. Cognition. 133(2):343-57.

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): 233-26. 

Image of boy with skull: NPS Photo/Nathan Kostegian

Image of preschool in Indore: Globe Tot'ers / wikimedia commons

Content of "Turning the tables to help kids learn math and science" last modified 4/2015.

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