Article : Critical Thinking in Math

Critical Thinking in Math

Critical thinking is a key factor in separating those students who can 'do' math from those who truly understand what they are doing. When students do math, they can perform computations, and they can explain concepts because they have learned formulas and definitions through practice and rote memorization. They don't necessarily know why the formula works, but they can use it. Likewise, they may not know how some ancient mathematician defined the concept, but they know the definition.

Students and teachers work together to think critically about solving math problems.

On the other hand, students who have been taught to think critically in math can explain why a formula works, and they can trace the steps used to define a concept. Not only can they solve a problem, they can explain the logic behind the process they used to reach a solution.

Think of it this way: sooner or later, most math students learn the Pythagorean Theorem and its related formula. Students can become adept at using the formula a^2 + b^2 = c^2 to find the length of the hypotenuse or one of the sides. They can solve problems involving right triangles using the formula, provided they are given enough information. Students who have been taught to think critically can explain why the Pythagorean Theorem works. More importantly, they know when and how to apply the Pythagorean Theorem to solve a problem even if right triangles aren't an obvious part of the solution.

Learning to apply the Pythagorean Theorem involves critical thinking.

Critical Thinking and Real World Problem Solving

Math textbooks only go so far when it comes to presenting real world problems that require mathematical solutions. Texts are organized around concepts making it easy for students to see what strategies they need to use to solve a problem. If the chapter is on the quadratic formula, then students automatically know they will use that formula at some point to answer every question, even a complex word problem.

Critical thinking kicks in when students have a variety of options for solving a problem. Students apply critical thinking to find the best strategy out of many possible methods to reach a solution.

Here's a problem that requires mathematical critical thinking: based on current trends in rising or falling temperatures, predict the average high and low temperatures for five different places on Earth five years from now. To solve the problem, students will need to analyze data, determine the trends in each place and select a method for predicting the future temperatures. They may need to use a variety of formulas and statistical tools to form their predictions. Teachers can take this a step further by asking students to explain and defend the methods they used.

Asking Questions

To think critically is to follow a clear line of logical steps and reasoning. To solve critical thinking problems, math teachers should model the way they think when solving a problem. Students can internalize a set of questions to ask that will help them think their way to a solution. These questions could include:

• What is the problem? What am I trying to figure out?
• What do I know? What is the given information?
• What do I need to know to solve the problem?
• What problems like this have I solved before?
• What solutions could work? What strategies will work best in this situation?

After students attempt a solution, they can further ask: Why did my solution work? Or, they might try to understand why their solution didn't work.

Critical thinking activities present the perfect opportunity for students to collaborate and have meaningful conversations using mathematical vocabulary, which is a good sign they have developed a deep understanding of concepts.