Teaching critical thinking:
An evidence-based guide
© 2009-2012 Gwen Dewar, Ph.D., all rights reserved
Teaching critical thinking? You might wonder if kids will work it out for themselves.
After all, lots of smart people have managed to think logically without formal instruction in logic. Moreover, studies show that kids become better learners when they are forced to explain how they solve problems. So maybe kids will discover principles of logic spontaneously, as they discuss their ideas with others.
But research hints at something else, too.
Perhaps the most effective way to foster critical thinking skills is to teach those skills. Explicitly. (Abrami et al 2008).
Studies suggest that students become remarkably better problem-solvers when we teach them to
- analyze analogies
- create categories and classify items appropriately
- identify relevant information
- construct and recognize valid deductive arguments
- test hypotheses
- recognize common reasoning fallacies
- distinguish between evidence and interpretations of evidence
Do such lessons stifle creativity? Not at all. Critical thinking is about curiosity, flexibility, and keeping an open mind (Quitadamo et al 2008). And, as Robert DeHaan has argued, creative problem solving depends on critical thinking skills (DeHaan 2009).
In fact, research suggests that explicit instruction in critical thinking may make kids smarter, more independent, and more creative.
Here are some examples--and some expert tips for teaching critical thinking to kids.
Teaching critical thinking may boost inventiveness and raise IQ
Richard Herrnstein and his colleagues gave over 400 seventh graders explicit instruction in critical thinking--a program that covered hypothesis testing, basic logic, and the evaluation of complex arguments, inventiveness, decision making, and other topics.
After sixty 45-minute lessons, the kids were tested on a variety of tasks, including tests the Otis-Lennon School Ability Test and Raven Progressive Matrices (both used to measure IQ). The project was remarkably effective.
Compared to students in a control group, the kids given critical thinking lessons made substantial and statistically significant improvements in language comprehension, inventive thinking, and even IQ (Herrnstein et al 1986).
Teaching critical thinking in science class may help kids solve everyday problems
In another experimental study, researchers Anat Zohar and colleagues tested 678 seventh graders’ analytical skills. Then they randomly assigned some students to receive critical thinking lessons as part of their biology curriculum.
Students in the experimental group were explicitly trained to recognize logical fallacies, analyze arguments, test hypotheses, and distinguish between evidence and the interpretation of evidence.
Students in a control group learned biology from the same textbook but got no special coaching in critical thinking.
At the end of the program, students were tested again. The students with critical thinking training showed greater improvement in their analytical skills, and not just for biology problems. The kids trained in critical thinking also did a better job solving everyday problems (Zohar et al 1994).
Tips for teaching critical thinking: What should parents and teachers do?
The short answer is make the principles of rational and scientific thinking explicit.
Philip Abrami and colleagues analyzed 117 studies about teaching critical thinking. The teaching approach with the strongest empirical support was explicit instruction--i.e., teaching kids specific ways to reason and solve problems. In studies where teachers asked students to solve problems without giving them explicit instruction, students experienced little improvement (Abrami et al 2008).
So it seems that kids benefit most when they are taught formal principles of reasoning. And the experiments mentioned above suggest that middle school students aren't too young to learn about logic, rationality, and the scientific method.
If your school isn’t teaching your child these things, then it might be a good idea to find some educational materials and work on critical thinking skills at home.
I also wonder about the need to counteract the forces of irrationality. As I’ve complained elsewhere, TV, books, “educational" software, and misinformed authority figures can discourage critical thinking in children.
What else can we do?
Recent research suggests that our schools can improve critical thinking skills by teaching kids the art of debate.
And at home, parents may consider these recommendations made by Peter Facione and a panel of experts convened by the American Philosophical Association (Facione 1990).
The American Philosophical Association's tips for teaching critical thinking
• Start early. Young children might not be ready for lessons in formal logic. But they can be taught to give reasons for their conclusions. And they can be taught to evaluate the reasons given by others. Wondering where to begin? If you have young child, check out these research-based tips for teaching critical thinking and scientific reasoning to preschoolers.
• Avoid pushing dogma. When we tell kids to do things in a certain way, we should give reasons.
• Encourage kids to ask questions. Parents and teachers should foster curiosity in children. If a rationale doesn’t make sense to a child, she should be encouraged to voice her objection or difficulty.
• Ask kids to consider alternative explanations and solutions. It’s nice to get the right answer. But many problems yield themselves to more than one solution. When kids consider multiple solutions, they may become more flexible thinkers.
• Get kids to clarify meaning. Kids should practice putting things in their own words (while keeping the meaning intact). And kids should be encouraged to make meaningful distinctions.
• Talk about biases. Even grade school students can understand how emotions, motives--even our cravings--can influence our judgments.
• Don’t confine critical thinking to purely factual or academic matters. Encourage kids to reason about ethical, moral, and public policy issues.
• Get kids to write. This last recommendation doesn’t come from Facione or the APA, but it makes good sense. As many teachers know, the process of writing helps students clarify their explanations and sharpen their arguments. In a recent study, researchers assigned college biology students to one of two groups. The writing group had to turn in written explanations of their laboratory work. The control group had to answer brief quizzes instead. At the end of the term, the students in the writing group had increased their analytical skills significantly. Students in the control group had not (Quitadamo and Kurtz 2007).
For more information about improving your child's problem-solving skills, be sure to check out my articles on intelligence in children and science education for kids.
References: Tips for teaching critical thinking to kids
Abrami PC, Bernard RM, Borokhovski E, Wadem A, Surkes M A, Tamim R, Zhang D. 2008. Instructional interventions affecting critical thinking skills and dispositions: a stage 1 meta-analysis. Rev. Educ. Res. 78:1102–1134.
DeHaan RL. 2009. Teaching creativity and inventive problem solving in science. CBE Life Sci. Educ. 8: 172-181.
Facione PA and the American Philosophical Association. 1990. Critical Thinking: A Statement of Expert Consensus for Purposes of Educational Assessment and Instruction. In: Research Findings and Recommendations, Millbrae, CA: Insight Assessment.
Herrnstein RJ, Nickerson RS, Sanchez M and Swets JA. 1986. Teaching thinking skills. American Psychologist 41: 1279-1289.
Quitadamo JJ, Faiola CL, Johnson JE and Kurtz MJ. 2008. Community-based inquiry improves critical thinking in general biology. CBE Life Sci. Educ. 7: 327-337.
Quitadamo IJ and Kurtz MJ. 2007. Learning to Improve: Using Writing to Increase Critical Thinking Performance in General Education Biology CBE Life Sci Educ 6(2): 140-154.
By the time your child is 8-years-old, he has firmly entered middle childhood. No longer a wide-eyed novice, he has a great many skills that he will continue to build on to expand his mental abilities in dramatic ways for the next several years. Named by the Swiss developmental psychologist Jean Piaget, the concrete operational period (as it is called) is the stage during which children begin applying logic and reasoning to concrete events. For example, recognizing that a person can feel tired even if it is not nighttime or understanding that just because it is night does not mean a person has to be tired. Children will also question concrete incongruities, such as being shown a video where a cat results from breeding 2 dogs. Concrete operational children begin using and manipulating symbols representationally with confidence (e.g., understanding that the symbol ‘+’ means to add together, while ‘x’ means to multiply). No longer dependent on manipulating objects in order to learn about them, children in this period demonstrate tremendous growth, both in and out of school. While still lacking the ability to fully understand abstract or hypothetical concepts (e.g., how a person who is a ‘minority’ can be in a situation where she would be the ‘majority’), 8-10 year olds are gaining a better understanding of a broad range of here-and-now mental activities.
Over the course of the concrete operational period (age 7-11), children master the ability to conserve. This ability means that they understand that certain properties of an object will remain the same, even if outward qualities change. For instance, by age 8, children understand that if there are two rows of five pennies, but one is spread so that the pennies are further apart, both rows still have the same total number of pennies. Ask a 4-year old or 5-year-old the same question and she will tell you the spread out row has more.
By 6 or 7, children can conserve both number (pennies, above) and liquid (knowing that a tall thin cup and short fat cup hold equal amounts). However, it is not until firmly within the concrete operational period that the same child will be able to conserve mass (knowing that if you break a clay ball into many parts, the weight is the same). Next comes the ability to conserve area (knowing that 4 Cheezits next to each other take up the same amount of area as four Cheezits spread around the placemat). Last to come online is the conservation of volume. In fact, many children do not understand that a clay ball reshaped and placed in water will not change the volume of water displaced until they are 11 or 12.
Over the course of the concrete operational period, children also begin to reason more accurately. For example, if (during the penny conservation task) they miscount the spread out row of pennies to be more than the other row, they will realize they made a mistake in counting. This realization is in contrast to believing that one row has more simply because it is spread out. Along with this ability comes an understanding of identity—that if nothing is added or taken away, or if only superficial aspects of a situation are changed, the inherent identity remains the same. For example, an 8-year-old understands that painting a white stripe on a black cat does not turn it into a skunk. Similarly, this same child can understand reversibility—that certain operations can reverse or negate the effects of others. For example, combining together a number of smaller clay balls will reverse the effects of breaking apart one larger one.
Concrete operations is a time when the brain goes through a number of significant changes. Information travels with greater speed through the nervous system and different parts of the brain begin to work in coordination with one another in new combinations. One result is that children this age begin to make logical arguments. Thus, it is not uncommon for your 8- or 9-year old to say, “Didn’t I read extra long last week? That means this week I can watch a movie instead of read.” Problem solving strategies also increase across this age. Now, children are able to use more than one strategy at a time, they can rehearse or preview actions better, and they are more accurate in their choice of strategy.
Similarly, children are able to understand that specific members of a set are also members of the more general set. Thus they can correctly answer the question: “Are there more dogs or black dogs?” because they realize that one set can include another. Try the Cablink app to help your child explore set membership. Seriation also comes online during concrete operations. Now, instead of using a haphazard method to organize items or information, children have the ability to use consistent criteria to order items.
Decentration is another hallmark of this stage. Thus, your child can now more successfully take another’s point of view and can consider more than one dimension simultaneously, as long as the considerations remain concrete. He can more effectively communicate about objects that the listener cannot see, and can think about how others perceive him. A fun way to foster perspective taking skills is with optical illusions. In addition, your child can understand more complex actions, such as when a person feels one way but acts another. These skills can also be seen in increased attention abilities. That is, children this age begin to understand that you can look at one thing (e.g., a picture) and yet be thinking about something else. Watch this video, which demonstrates how looking for (paying attention to) one thing limits your ability to look for (pay attention to) something else. As a result, they learn that they can shift and focus their attention with greater control than previously.
In summary, between 8-10 years old, children learn to mentally combine, separate, order, and transform objects and actions. They learn to conserve mass and area, with many also learning to conserve volume. Their ability to apply logic and reason increases, as does their ability to focus attention. They can consider multiple perspectives and apply various thought-out strategies. And while they continue to struggle with understanding abstract or hypothetical concepts, children this age can apply mental operations to concrete problems, objects, and events.