English:Critical Thinking Basics
Critical Thinking Basics
Introduction
Every day, you make choices about what to believe, what to do, and how to solve problems. Critical thinking helps you slow down, ask useful questions, look for evidence, compare ideas, and explain your reasons. It does not mean criticizing everything. It means thinking carefully and fairly before you decide.
In this aiMOOC, you will practise critical thinking through questions, puzzles, short investigations, discussions, and creative projects. You will learn how to tell a fact from an opinion, check a source, notice bias, compare different perspectives, and use evidence to support a conclusion.
By the end, you should be able to explain not only what you think, but also why you think it.
What Critical Thinking Means
Critical thinking is careful thinking that uses information and reasons. A critical thinker does not rush to accept the first answer. Instead, you ask questions such as: What do I know? How do I know it? What evidence is there? Is another explanation possible?
You do not need to be an expert to think critically. You need curiosity, patience, and a willingness to change your mind when stronger evidence appears.
Think Like a Detective
A detective looks for clues before reaching a conclusion. You can do the same with schoolwork, online information, everyday problems, and disagreements.
A useful thinking routine is:
| Thinking move | What you do |
|---|---|
| Ask | Turn a statement or problem into useful questions. |
| Gather | Find facts, examples, observations, or other information. |
| Check | Decide whether the information and its source are trustworthy. |
| Compare | Look for similarities, differences, patterns, and other possible explanations. |
| Decide | Choose the conclusion or action best supported by what you know. |
| Explain | Give clear reasons and point to the evidence that supports them. |
Asking Better Questions
Good questions open up thinking. A question such as Is this true? is useful, but you can often go further.
Clarifying questions help you understand a claim: What exactly do you mean?
Evidence questions ask for support: What facts or examples show this?
Source questions investigate where information came from: Who created this, and how might they know?
Perspective questions look for other viewpoints: Who might see this differently, and why?
Consequence questions explore possible results: What could happen if we choose this option?
In class discussions, strong questions are not tricks. They help everyone understand an idea more clearly.
Facts, Opinions, Claims, and Evidence
A fact is a statement that can be checked against reliable evidence. An opinion expresses a belief, preference, or judgment. An opinion can be reasonable, but it is not automatically a fact.
A claim is a statement someone wants you to accept. Claims can be true, false, partly true, uncertain, or impossible to check with the information available.
Evidence is information that supports or challenges a claim. Evidence can include measurements, observations, documents, photographs, records, or well-supported expert explanations. Strong evidence should be relevant to the exact claim you are checking.
Imagine someone says, Our class learns better outside. That is a claim. To investigate it, you could compare work completed indoors and outdoors, ask classmates about concentration, and think about other factors such as noise, weather, and the type of lesson.
Checking Sources and Online Information
A source is where information comes from. Sources include books, websites, videos, people, surveys, photographs, and scientific studies. Before trusting a source, ask who created it, when it was created, what evidence it gives, and whether other reliable sources agree.
Online, a polished page or confident speaker can still be wrong. A large number of likes or shares also does not prove that a claim is true.
When you check online information, try to:
- Identify the source: Find the author or organization and look for relevant expertise.
- Check the evidence: Look for facts, data, examples, or links that actually support the claim.
- Compare sources: See whether other trustworthy sources independently report the same thing.
- Check the date: Old information may no longer describe the current situation.
- Notice purpose and bias: Ask whether the message is trying mainly to inform, persuade, entertain, or sell something.
Comparing Information
Critical thinkers compare information instead of looking at one piece in isolation. You can compare two stories, two solutions, two experiments, or two sources.
A Venn diagram is one tool for sorting similarities and differences. Information in the overlapping part belongs to both groups.
When you compare ideas, use the same questions for each one. For example: What is the main claim? What evidence is offered? What is missing? What are the strengths and weaknesses? Fair comparison helps you avoid choosing a favorite too early.
Different Perspectives
Two people can look at the same situation and notice different things. A perspective is a way of viewing or understanding something. Different perspectives do not mean that every answer is equally correct, but they can reveal information you missed.
What do you see first in the image: a duck or a rabbit? The lines do not change, but your interpretation can change. In real problems, perspectives can differ because people have different experiences, goals, roles, or information.
A strong critical thinker can say, Here is my view, here is my reason, and here is another view I should consider.
Bias and Assumptions
A bias is a tendency that can pull our judgment in one direction. Everyone can have biases. For example, you may notice information that supports a favorite team and ignore information that does not.
An assumption is something you accept without checking it first. Some assumptions are harmless, but others can cause mistakes.
Suppose a group project is late and you think, Sam did not care. That may be an assumption. Other explanations are possible: Sam may have misunderstood the deadline, had a technical problem, or been absent. Critical thinking means checking before blaming.
One useful habit is to ask: What am I assuming? What evidence would change my mind?
Reasoning: Connecting Evidence to Conclusions
Reasoning is the process of connecting what you know to what you conclude. Good reasoning makes the connection clear.
For example:
Evidence: The playground is wet, several students are carrying umbrellas, and dark clouds are moving away.
Conclusion: It probably rained recently.
This conclusion is reasonable, but it is not certain. A sprinkler could have made the playground wet. Critical thinkers often use words such as probably, possibly, and based on the evidence when certainty is limited.
Be careful with cause and effect. If two things happen together, one does not always cause the other. You need more evidence before saying, A caused B.
Solving Problems and Making Decisions
Critical thinking is useful when there is no obvious answer. Imagine your class has a small budget for one new activity: a class garden, a board-game set, or art materials.
You could:
- Define the problem: What are you trying to achieve?
- Choose criteria: Cost, usefulness, number of students served, learning value, and maintenance might matter.
- Compare options: Use the same criteria for every choice.
- Gather information: Check prices, space, safety, and student interest.
- Make and explain a decision: Choose the option that best fits the evidence and criteria.
A good decision is not simply the option you liked first. It is a choice you can explain with reasons.
Discussing Ideas Fairly
Critical thinking works best when people can disagree respectfully. Attack the idea, not the person. Listen carefully enough to explain the other person's view before answering it.
Useful discussion phrases include: What evidence supports that?, I see it differently because..., Could there be another explanation?, and I changed my mind because...
Changing your mind after seeing better evidence is a strength. It shows that your goal is understanding, not simply winning.
A Mini Investigation
Read this claim: "Students remember more when every lesson includes a game."
Before deciding whether you agree, think like an investigator. What does remember more mean? Does the claim mean every student, every lesson, and every kind of game? What evidence would you need? How could you compare learning with and without a game? What other factors could affect the result?
This example shows why careful thinkers define words, test claims, and avoid conclusions that are broader than the evidence.
Interactive Tasks
Quiz: Test Your Knowledge
What is the main purpose of critical thinking? (To make careful judgments using evidence and reasons) (!To disagree with every idea) (!To answer as quickly as possible) (!To memorize every fact)
Which question best checks evidence? (What facts support this claim) (!Do I already like this idea) (!How many people shared it) (!Can I repeat it loudly)
Which statement best describes an opinion? (It expresses a belief preference or judgment) (!It is always proven by measurement) (!It can never change) (!It must be accepted by everyone)
What should you do first when an online claim seems surprising? (Check the source and supporting evidence) (!Share it immediately) (!Assume the title proves it) (!Trust it because it has pictures)
Why can comparing several reliable sources help? (It can show whether information is supported independently) (!It guarantees every source says exactly the same words) (!It removes the need to think) (!It makes old information current)
What is an assumption? (Something accepted without checking it first) (!A measurement made with a tool) (!A source listed at the end of a book) (!A conclusion supported by many tests)
What is a perspective? (A way of viewing or understanding something) (!A list of website passwords) (!A mathematical answer key) (!A rule that every person must agree)
Which action shows good reasoning? (Explaining how evidence supports a conclusion) (!Ignoring evidence that challenges your idea) (!Choosing the first answer you hear) (!Changing a fact to fit your opinion)
Why should you be careful about cause and effect? (Two events happening together do not always mean one caused the other) (!Causes can never be investigated) (!Effects always happen before causes) (!Every event has only one possible cause)
What shows strong critical thinking during a disagreement? (Listening to another view and responding with reasons) (!Insulting the person who disagrees) (!Repeating your opinion without evidence) (!Refusing to change your mind)
Memory Game
| Evidence | Information that supports or challenges a claim |
| Source | The place or person information comes from |
| Claim | A statement someone wants you to accept |
| Bias | A tendency that can pull judgment in one direction |
| Inference | A conclusion reached from clues and reasoning |
| Perspective | A particular way of viewing a situation |
Drag and Drop
| Match the correct terms. | Topic |
|---|---|
| Evidence question | What proof supports this claim |
| Source question | Who created this information |
| Perspective question | Who might see this differently |
| Consequence question | What could happen after this choice |
| Clarifying question | What exactly does this statement mean |
...
Crossword Puzzle
| Evidence | What supports or challenges a claim |
| Source | Where information comes from |
| Reasoning | What connects evidence to a conclusion |
| Opinion | A belief preference or judgment |
| Perspective | A way of viewing a situation |
| Assumption | Something accepted before it is checked |
LearningApps
Cloze Text
Open-Ended Tasks
Easy
- Question Detective: Choose an everyday claim and write five useful questions that would help you understand or check it.
- Fact or Opinion Hunt: Collect eight sentences from classroom materials or safe websites and sort them into facts and opinions, explaining two difficult choices.
- Perspective Sketch: Draw one situation from two different viewpoints and add a short caption explaining what each person might notice.
- Evidence Snapshot: Photograph or draw three examples of evidence you could use to answer a simple question about your school or home environment.
Standard
- Source Check: Compare two age-appropriate web pages about the same topic and create a one-page source-check report about author, date, evidence, and purpose.
- Mini Interview: Interview two people about the same school issue, summarize their perspectives, and identify one point they share and one point where they differ.
- Decision Matrix: Compare three choices for a class activity using at least four fair criteria, then explain your final decision.
- Claim Testing: Design a small safe investigation to test a claim such as which paper airplane design flies farther, record observations, and explain what the results do and do not show.
Advanced
- Media Detective Video: Create a short video that teaches classmates how to check a surprising online claim without naming or embarrassing real people.
- Bias Investigation: Find two advertisements for similar products, identify persuasive techniques and possible bias, and redesign one ad to be more informative.
- Classroom Debate Map: Choose a school-related question, gather reasons and evidence for at least two sides, and create a visual map before giving your own conclusion.
- Critical Thinking Exhibition: Build a mini exhibition with a poster, puzzle, comparison chart, and reflection showing how evidence, questions, perspectives, and reasoning work together.
Learning Assessment
- Evidence-Based Conclusion: Read a short set of mixed facts and opinions, select the most relevant evidence, and write a conclusion that explains why that evidence matters.
- Source Reliability Comparison: Compare two sources about the same claim and judge which is more trustworthy by applying author, evidence, date, purpose, and corroboration checks.
- Reasoning Repair: Examine an argument with a weak connection between evidence and conclusion, identify the problem, and rewrite the reasoning so it becomes stronger.
- Multiple Perspectives Analysis: Explain how two people could interpret the same event differently, then decide which parts can be checked as facts and which depend on viewpoint.
- Cause and Effect Challenge: Evaluate a claim that one event caused another and describe what extra evidence would be needed before accepting the causal conclusion.
- Transfer Task: Apply the critical-thinking routine to a new real-life decision, document your questions and evidence, compare options, and justify your final choice.
Evidence of Learning
Evidence that you have learned the basics of critical thinking can include several kinds of achievement.
Knowledge: You can explain claims, evidence, sources, facts, opinions, perspectives, bias, assumptions, reasoning, and cause-and-effect questions in your own words.
Skills: You can ask useful questions, check a source, compare information fairly, separate evidence from opinion, notice possible bias, consider another perspective, and connect evidence to a conclusion.
Products: Your work may include investigation notes, comparison charts, interviews, drawings, decision matrices, short videos, source checks, debates, or project displays.
Transfer: You can use critical thinking outside a single lesson, for example when reading online information, solving a group problem, choosing between options, discussing a disagreement, or deciding whether a claim is trustworthy.
Reflection: You can explain when and why you changed your mind, what evidence influenced you, and what you would investigate next.
OERs on the Topic
Linked Learning Areas
Critical thinking connects strongly with English language arts, Media literacy, Science education, Mathematics education, Civics, Digital literacy, and everyday problem solving. In English lessons, you use it when you interpret texts and support ideas with evidence. In science and mathematics, you use it when you examine data, test explanations, and check whether a solution makes sense. In media and civic learning, you use it when you judge sources, claims, and persuasive messages.