Teaching students to be critical thinkers is perhaps the most important goal in education. All teachers, regardless of subject area, contribute to the process of teaching students to think for themselves. However, it’s not always an easy skill to teach. Students need guidance and practice with critical thinking strategies at every level.

One problem with teaching critical thinking is that many different definitions of this skill exist. The Foundation for Critical Thinking offers four different definitions of the concept. Essentially, critical thinking is the ability to evaluate information and decide what we think about that information, a cumulative portfolio of skills our students need to be successful problem solvers in an ever-changing world.

Here is a list of 50 classroom strategies for teachers to use to foster critical thinking among students of all ages.

1. Don’t give them the answers  

Learning is supposed to be hard, and while it may be tempting to jump in and direct students to the right answer, it’s better to let them work through a problem on their own. A good teacher is a guide, not an answer key. The goal is to help students work at their “challenge” level, as opposed to their “frustration” level.

2. Controversial issue barometer

In this activity, a line is drawn down the center of the classroom. The middle represents the neutral ground, and the ends of the line represent extremes of an issue. The teacher selects an issue and students space themselves along the line according to their opinions. Being able to articulate opinions and participate in civil discourse are important aspects of critical thinking.

3. Play devil’s advocate

During a robust classroom discussion, an effective teacher challenges students by acting as devil’s advocate, no matter their personal opinion. “I don’t care WHAT you think, I just care THAT you think” is my classroom mantra. Critical thinking strategies that ask students to analyze both sides of an issue help create understanding and empathy.

4. Gallery walk

In a gallery walk, the teacher hangs images around the classroom related to the unit at hand (photographs, political cartoons, paintings). Students peruse the artwork much like they are in a museum, writing down their thoughts about each piece.

5. Review something

A movie, TV show, a book, a restaurant, a pep assembly, today’s lesson – anything can be reviewed. Writing a review involves the complex skill of summary without spoilers and asks students to share their opinion and back it up with evidence.

6. Draw analogies

Pick two unrelated things and ask students how those things are alike (for example, how is a museum like a snowstorm). The goal here is to encourage creativity and look for similarities.

7. Think of 25 uses for an everyday thing

Pick an everyday object (I use my camera tripod) and set a timer for five minutes. Challenge students to come up with 25 things they can use the object for within that time frame. The obvious answers will be exhausted quickly, so ridiculous answers such as “coatrack” and “stool” are encouraged.

8. Incorporate riddles

Students love riddles. You could pose a question at the beginning of the week and allow students to ask questions about it all week.

9. Crosswords and sudoku puzzles

The games section of the newspaper provides great brainteasers for students who finish their work early and need some extra brain stimulation.

10. Fine tune questioning techniques

A vibrant classroom discussion is made even better by a teacher who asks excellent, provocative questions. Questions should move beyond those with concrete answers to a place where students must examine why they think the way they do.

11. Socratic seminar

The Socratic seminar is perhaps the ultimate critical thinking activity. Students are given a universal question, such as “Do you believe it is acceptable to break the law if you believe the law is wrong?” They are given time to prepare and answer, and then, seated in a circle, students are directed to discuss the topic. Whereas the goal of a debate is to win, the goal of a Socratic discussion is for the group to reach greater understanding.

12. Inquiry based learning

In inquiry-based learning, students develop questions they want answers to, which drives the curriculum toward issues they care about. An engaged learner is an essential step in critical thinking.

13. Problem-based learning

In problem-based learning, students are given a problem and asked to develop research-based solutions. The problem can be a school problem (the lunchroom is overcrowded) or a global problem (sea levels are rising).

14. Challenge all assumptions

The teacher must model this before students learn to apply this skill on their own. In this strategy, a teacher helps a student understand where his or her ingrained beliefs come from. Perhaps a student tells you they believe that stereotypes exist because they are true. An effective teacher can ask “Why do you think that?” and keep exploring the issue as students delve into the root of their beliefs. Question everything.

15. Emphasize data over beliefs

Data does not always support our beliefs, so our first priority must be to seek out data before drawing conclusions.

16. Teach confirmation bias

Confirmation bias is the human tendency to seek out information that confirms what we already believe, rather than letting the data inform our conclusions. Understanding that this phenomenon exists can help students avoid it.

17. Visualization

Help students make a plan before tackling a task.

18. Mind mapping

Mind mapping is a visual way to organize information. Students start with a central concept and create a web with subtopics that radiate outward.

19. Develop empathy

Empathy is often cited as an aspect of critical thinking. To do so, encourage students to think from a different point of view. They might write a “con” essay when they believe the “pro,” or write a letter from someone else’s perspective.

20. Summarization

Summarizing means taking all the information given and presenting it in a shortened fashion.

21. Encapsulation

Encapsulation is a skill different from summarization. To encapsulate a topic, students must learn about it and then distill it down to its most relevant points, which means students are forming judgements about what is most and least important.

22. Weigh cause and effect

The process of examining cause and effect helps students develop critical thinking skills by thinking through the natural consequences of a given choice.

23. Problems in a jar

Perfect for a bell-ringer, a teacher can stuff a mason jar with dilemmas that their students might face, such as, “Your best friend is refusing to talk to you today. What do you do?” Then, discuss possible answers. This works well for ethical dilemmas, too.

24. Transform one thing into another

Give students an object, like a pencil or a mug. Define its everyday use (to write or to drink from). Then, tell the students to transform the object into something with an entirely separate use. Now what is it used for?

25. Which one doesn’t belong?

Group items together and ask students to find the one that doesn’t belong. In first grade, this might be a grouping of vowels and a consonant; in high school, it might be heavy metals and a noble gas.

26. Compare/contrast

Compare and contrast are important critical thinking strategies. Students can create a Venn diagram to show similarities or differences, or they could write a good old-fashioned compare/contrast essay about the characters of Romeo and Juliet.

27. Pick a word, find a related word

This is another fun bell-ringer activity. The teacher starts with any word, and students go around the room and say another word related to that one. The obvious words go quickly, meaning the longer the game goes on, the more out-of-the-box the thinking gets.

28. Ranking of sources

Give students a research topic and tell them to find three sources (books, YouTube videos, websites). Then ask them, what resource is best – and why.

29. Hypothesize

The very act of hypothesizing is critical thinking in action. Students are using what they know to find an answer to something they don’t know.

30. Guess what will happen next

This works for scientific reactions, novels, current events, and more. Simply spell out what we know so far and ask students “and then what?”

31. Practice inference

Inference is the art of making an educated guess based on evidence presented and is an important component of critical thinking.

32. Connect text to self

Ask students to draw connections between what they are reading about to something happening in their world. For example, if their class is studying global warming, researching how global warming might impact their hometown will help make their studies relevant.

33. Levels of questioning

There are several levels of questions (as few as three and as many as six, depending on who you ask). These include factual questions, which have a right or wrong answer (most math problems are factual questions). There are also inferential questions, which ask students to make inferences based on both opinion and textual evidence. Additionally, there are universal questions, which are “big picture” questions where there are no right or wrong answers.

Students should practice answering all levels of questions and writing their own questions, too.

34. Demand precise language

An expansive vocabulary allows a student to express themselves more exactly, and precision is a major tool in the critical thinking toolkit.

35. Identify bias and hidden agendas

Helping students to critically examine biases in sources will help them evaluate the trustworthiness of their sources.

36. Identify unanswered questions

After a unit of study is conducted, lead students through a discussion of what questions remain unanswered. In this way, students can work to develop a lifelong learner mentality.

37. Relate a topic in one subject area to other disciplines

Have students take something they are studying in your class and relate it to other disciplines. For example, if you are studying the Civil War in social studies, perhaps they could look up historical fiction novels set during the Civil War era or research medical advancements from the time period for science.

38. Have a question conversation

Start with a general question and students must answer your question with a question of their own. Keep the conversation going.

39. Display a picture for 30 seconds, then take it down

Have students list everything they can remember. This helps students train their memories and increases their ability to notice details.

40. Brainstorm, free-write

Brainstorming and freewriting are critical thinking strategies to get ideas on paper. In brainstorming, anything goes, no matter how off-the-wall. These are great tools to get ideas flowing that can then be used to inform research.

41. Step outside your comfort zone

Direct students to learn about a topic they have no interest in or find particularly challenging. In this case, their perseverance is being developed as they do something that is difficult for them.

42. The answer is, the question might be

This is another bell-ringer game that’s great for engaging those brains. You give students the answer and they come up with what the question might be.

43. Cooperative learning

Group work is a critical thinking staple because it teaches students that there is no one right way to approach a problem and that other opinions are equally valid.

44. What? So what? Now what?

After concluding a unit of study, these three question frames can be used to help students contextualize their learning.

45. Reflection

Ask students to reflect on their work – specifically, how they can improve moving forward.

46. Classify and categorize

These are higher level Bloom’s tasks for a reason. Categorizing requires students to think about like traits and rank them in order of importance.

47. Role play

Roleplay allows students to practice creative thinking strategies. Here, students assume a role and act accordingly.

48. Set goals

Have students set concrete, measurable goals in your class so they understand why what they do matters.

49. Read

No matter your subject area, encourage students to read voraciously. Through reading they will be exposed to new ideas, new perspectives, and their worlds will grow.

50. Cultivate curiosity

A curious mind is an engaged mind. Students should be encouraged to perform inquiry simply for the sake that it is a joy to learn about something we care about.

50 Critical Thinking Strategies - Cover Draft