Evaluating Sources
Learn to judge sources for a research project by asking who wrote it, when, why, and whether it checks out against an independent source — with examples and practice.
What you'll do in this lesson
A voice-first session with the Crimsora tutor on Evaluating Sources, then targeted practice and FRQs — with the tutor adapting to where you get stuck.
What this lesson covers
You have a research question and a screen full of results. Every one of them looks confident. Some are careful, some are careless, and a few are trying to sell you something. Your job in this lesson is to stop treating "I found it online" as proof and start treating every source as a claim that has to earn your trust.
Four questions do most of the work: Who wrote it? When was it written? Why was it written? And can it be checked against a separate, independent source? Answering those four turns a vague feeling of "this seems fine" into evidence you can defend when a classmate or your teacher asks how you know. You will also learn something researchers know well: a source can be perfectly trustworthy and still be the wrong source for your particular question.
Four questions do most of the work: Who wrote it? When was it written? Why was it written? And can it be checked against a separate, independent source? Answering those four turns a vague feeling of "this seems fine" into evidence you can defend when a classmate or your teacher asks how you know. You will also learn something researchers know well: a source can be perfectly trustworthy and still be the wrong source for your particular question.
The Four Questions Every Source Has to Answer
Evaluating a source is not a mood; it is a short interrogation. Before you take a single note, run the source through four checks.
Who wrote it? Look for a named author and a reason to believe that person knows the subject — a job title, a degree, years of experience, a research position, or first-hand involvement. "Staff" or no name at all is not automatically fatal, but it shifts the burden: now the organization behind the page has to be the thing you trust.
When was it written? Find a publication or last-updated date. How much age matters depends on the topic. A 1998 article on the Underground Railroad may still be excellent; a 1998 article on teen social media use is a historical artifact, not current evidence.
Why was it written? Every text has a purpose: to inform, to persuade, to entertain, or to sell. Purpose is not the same as dishonesty, but it tells you what the writer had reason to leave out.
Can it be checked? Does the source cite where its facts came from, and can you find the same claim in a source that did not simply copy this one?
Who wrote it? Look for a named author and a reason to believe that person knows the subject — a job title, a degree, years of experience, a research position, or first-hand involvement. "Staff" or no name at all is not automatically fatal, but it shifts the burden: now the organization behind the page has to be the thing you trust.
When was it written? Find a publication or last-updated date. How much age matters depends on the topic. A 1998 article on the Underground Railroad may still be excellent; a 1998 article on teen social media use is a historical artifact, not current evidence.
Why was it written? Every text has a purpose: to inform, to persuade, to entertain, or to sell. Purpose is not the same as dishonesty, but it tells you what the writer had reason to leave out.
Can it be checked? Does the source cite where its facts came from, and can you find the same claim in a source that did not simply copy this one?
| Question | What you look for | Warning sign |
|---|---|---|
| Who? | Named author, relevant expertise | No author, no organization, no way to tell |
| When? | Clear date, recent enough for the topic | Undated page, dead links, outdated numbers |
| Why? | Stated purpose, balanced treatment | Product links, all-caps outrage, one-sided claims |
| Checkable? | Citations, links to data, quoted experts | "Studies show" with no study named |
Reading the Author and the Purpose Together
Students often check the author's credentials and stop there. Expertise and motive have to be read together, because a genuine expert can still be an interested party.
Suppose you are researching whether energy drinks are safe for teenagers. A cardiologist who studies caffeine is a strong author. A cardiologist who studies caffeine and is quoted on the website of an energy drink company is the same expert speaking in a place with a purpose. That does not prove the quotation is false. It means you should find the doctor's actual published statement rather than trusting the company's version of it.
The reverse also matters. Someone with no formal credentials can still be a valuable source when the question is about experience rather than science. For a research question about what it feels like to move to a new country as a child, a first-hand account from a person who did it is exactly the right evidence, credentials or not.
Watch for these purpose clues: a "Buy now" button, a donation appeal, language that treats one side as obviously stupid, or a headline that promises a shocking secret. Also watch for the opposite trap — assuming a calm, tidy-looking page must be neutral. Design is cheap. A polished site with no author, no date, and no sources is less trustworthy than a plain-looking page from a university library.
Where students most often go wrong: judging a source by whether they already agree with it. If you only test the sources you dislike, you are not evaluating, you are defending. Run the same four questions on the source that supports your opinion.
Suppose you are researching whether energy drinks are safe for teenagers. A cardiologist who studies caffeine is a strong author. A cardiologist who studies caffeine and is quoted on the website of an energy drink company is the same expert speaking in a place with a purpose. That does not prove the quotation is false. It means you should find the doctor's actual published statement rather than trusting the company's version of it.
The reverse also matters. Someone with no formal credentials can still be a valuable source when the question is about experience rather than science. For a research question about what it feels like to move to a new country as a child, a first-hand account from a person who did it is exactly the right evidence, credentials or not.
Watch for these purpose clues: a "Buy now" button, a donation appeal, language that treats one side as obviously stupid, or a headline that promises a shocking secret. Also watch for the opposite trap — assuming a calm, tidy-looking page must be neutral. Design is cheap. A polished site with no author, no date, and no sources is less trustworthy than a plain-looking page from a university library.
Where students most often go wrong: judging a source by whether they already agree with it. If you only test the sources you dislike, you are not evaluating, you are defending. Run the same four questions on the source that supports your opinion.
Cross-Checking Against an Independent Source
The single strongest move in source evaluation is corroboration: finding the same claim in a source that arrived at it separately.
The word independent is doing heavy lifting. Ten websites repeating one number are not ten pieces of evidence — they are one piece of evidence copied nine times. Before you count a match, ask where each source got the claim. If four articles all trace back to the same news report, you have one source and four echoes. Real corroboration means a different researcher, a different data set, or a different eyewitness reached the same conclusion.
A practical routine: pick the most specific factual claim in your source — a number, a date, a quotation — and search for that claim by itself. Three things can happen. You find it confirmed in a separate, reputable place, and your confidence rises. You find nothing, which is a reason to hold the claim loosely rather than build a paragraph on it. Or you find the claim contradicted, which means you now have a new research task: figure out which source is better documented and why they differ.
When credible sources genuinely disagree, do not quietly pick the one you like. Say so in your writing. A sentence such as "Two studies report different results, and the more recent one used a larger sample" shows real research thinking.
A final habit worth building: click through to the original. When an article says "a recent study found," follow the link. Sometimes the study says something narrower than the headline claims, and noticing that gap is exactly the skill this lesson is building.
The word independent is doing heavy lifting. Ten websites repeating one number are not ten pieces of evidence — they are one piece of evidence copied nine times. Before you count a match, ask where each source got the claim. If four articles all trace back to the same news report, you have one source and four echoes. Real corroboration means a different researcher, a different data set, or a different eyewitness reached the same conclusion.
A practical routine: pick the most specific factual claim in your source — a number, a date, a quotation — and search for that claim by itself. Three things can happen. You find it confirmed in a separate, reputable place, and your confidence rises. You find nothing, which is a reason to hold the claim loosely rather than build a paragraph on it. Or you find the claim contradicted, which means you now have a new research task: figure out which source is better documented and why they differ.
When credible sources genuinely disagree, do not quietly pick the one you like. Say so in your writing. A sentence such as "Two studies report different results, and the more recent one used a larger sample" shows real research thinking.
A final habit worth building: click through to the original. When an article says "a recent study found," follow the link. Sometimes the study says something narrower than the headline claims, and noticing that gap is exactly the skill this lesson is building.
Trustworthy For What? Matching the Source to the Question
Credibility is not a property a source carries around by itself. It is always credibility for a specific question.
A restaurant's own website is a poor source for "is this the best restaurant in town" and an excellent source for "what hours is it open." A political campaign's site is biased evidence about the opponent and reliable evidence about what the candidate claims to believe. A middle school student's blog post is weak evidence about vaccine chemistry and strong evidence about how a seventh grader experienced remote learning. Same source, different question, different verdict.
So after the four checks, ask one more: does this source actually speak to my question, and does it speak to it in the way I need? A source can be current, expert, and honest, and still be about a neighboring topic. Using it anyway is one of the most common problems in student research papers — the evidence is real, but it does not support the sentence it is attached to.
Use general reference sources as a starting point, then follow their citations to the specific, checkable sources you will actually quote. That path — background first, evidence second — is how experienced researchers work, and it is what makes the quoting and citing you do later in this unit worth doing.
A restaurant's own website is a poor source for "is this the best restaurant in town" and an excellent source for "what hours is it open." A political campaign's site is biased evidence about the opponent and reliable evidence about what the candidate claims to believe. A middle school student's blog post is weak evidence about vaccine chemistry and strong evidence about how a seventh grader experienced remote learning. Same source, different question, different verdict.
So after the four checks, ask one more: does this source actually speak to my question, and does it speak to it in the way I need? A source can be current, expert, and honest, and still be about a neighboring topic. Using it anyway is one of the most common problems in student research papers — the evidence is real, but it does not support the sentence it is attached to.
| Source | Good for | Not good for |
|---|---|---|
| Government health agency page | Official guidelines and statistics | Personal experiences of patients |
| Interview with a local coach | What one program does and why | Nationwide trends |
| Company press release | The company's own plans | Whether the product works |
| Encyclopedia entry | Background and key terms | Detailed evidence for a claim |
Key terms
- Credibility.
- The degree to which a source deserves to be believed, based on the author's expertise, the publication's standards, the evidence given, and the absence of a motive to mislead.
- Accuracy.
- Whether the specific facts in a source are correct and verifiable, judged by checking them against evidence from somewhere else.
- Corroboration.
- Confirming a claim by finding it in an independent source that did not simply copy the first one.
- Bias.
- A leaning toward one side or outcome that shapes what a source includes, emphasizes, or leaves out. Bias makes a source one-sided; it does not automatically make it false.
- Purpose.
- The reason a text was created — to inform, persuade, entertain, or sell. Purpose predicts what the writer had reason to omit.
- Currency.
- How recent a source is, and whether that recency matters for the topic being researched.
- Primary source.
- A first-hand record created by someone directly involved — a diary, interview, photograph, original study, or eyewitness account.
- Secondary source.
- A text that describes, analyzes, or summarizes primary sources, such as a news article about a study or a textbook chapter.
Worked example
Maya's research question is: Should middle schools start the school day later than 8:00 a.m.? She finds a web page titled "Later Start Times Boost Teen Grades!" It has no author name, a small line reading "Updated 2011," a sidebar advertising blackout curtains, and this sentence: "Studies show teens who start school later sleep 90 minutes more per night." Should Maya use it?
Run the four questions in order.
Who wrote it? No author is named, and the page does not identify an organization or its expertise. Maya cannot tell whether a sleep researcher or an anonymous marketer wrote it. This is not yet a reason to reject the page, but nothing on it has earned trust.
When was it written? "Updated 2011" is more than a decade old, and school schedules and sleep research have both moved since then. For a question about what schools should do now, that age matters.
Why was it written? The exclamation-point headline and the curtain advertisement point toward selling and attention, not informing. A page that profits when readers believe teens sleep badly has an interest in the claim it is making.
Can it be checked? "Studies show" names no study, no researcher, and no year, so there is nothing to follow. Maya searches the specific claim — 90 minutes of extra sleep with later start times — and finds a published study reported by a university news office that gives a smaller figure and describes the schools it examined.
Decision. Maya does not cite the web page. She cites the university-reported study instead, because it has a named research team, a recent date, an informing purpose, and methods she can describe. The original page still did one useful thing: it pointed her toward a claim worth checking. That is a fine use for a weak source — as a lead, never as evidence.
Who wrote it? No author is named, and the page does not identify an organization or its expertise. Maya cannot tell whether a sleep researcher or an anonymous marketer wrote it. This is not yet a reason to reject the page, but nothing on it has earned trust.
When was it written? "Updated 2011" is more than a decade old, and school schedules and sleep research have both moved since then. For a question about what schools should do now, that age matters.
Why was it written? The exclamation-point headline and the curtain advertisement point toward selling and attention, not informing. A page that profits when readers believe teens sleep badly has an interest in the claim it is making.
Can it be checked? "Studies show" names no study, no researcher, and no year, so there is nothing to follow. Maya searches the specific claim — 90 minutes of extra sleep with later start times — and finds a published study reported by a university news office that gives a smaller figure and describes the schools it examined.
Decision. Maya does not cite the web page. She cites the university-reported study instead, because it has a named research team, a recent date, an informing purpose, and methods she can describe. The original page still did one useful thing: it pointed her toward a claim worth checking. That is a fine use for a weak source — as a lead, never as evidence.
Practice questions
Devon is researching how a new city bike-lane project has affected traffic. Which source is most trustworthy for the question of whether accidents went down after the lanes were built?
- A press release from the construction company that built the bike lanes
- A city transportation department report comparing accident counts before and after, published this year
- A comment on a neighborhood message board from someone who bikes to work daily
- A 2009 magazine article about bike lanes in a different country
Answer: A city transportation department report comparing accident counts before and after, published this year
Test each option against the four questions. The construction company has a clear interest in the project looking successful, so its purpose weakens it as evidence about results. The message board comment is a real experience but one person's impression, not a count of accidents. The 2009 article fails both currency and relevance — different decade, different city. The department report names the agency responsible, is current, exists to inform rather than promote, and reports data another researcher could check. That combination of authorship, date, purpose, and verifiability makes it the strongest fit for this specific question.
A student says, "I know my source is accurate because I found the exact same sentence on five different websites." Explain why this reasoning is weaker than it sounds, and describe what the student should do instead.
Answer: Repetition is not corroboration when the sources are not independent. Identical wording across five sites suggests they all copied one original, so the student really has one source repeated five times. The student should trace the claim back to its origin and then look for a separate source — a different study, agency, or eyewitness — that reached the same conclusion on its own.
The key idea is independence. Copying spreads a claim without ever testing it, so a false statement can appear on hundreds of pages and still have zero supporting evidence behind it. The tell here is the phrase "the exact same sentence": identical wording is a signature of copying, not of separate confirmation. A strong answer names that clue, explains why echoes do not add evidence, and gives a concrete next step — find the original, then look for a genuinely separate source. A complete response might also note that if no independent source can be found, the student should treat the claim cautiously rather than building an argument on it.
Marisol is writing about what it was like to be a student during the 1960s school integration movement. She finds a personal memoir written in 1998 by a woman who was one of the first Black students at her high school in 1963. Marisol worries the memoir is "too old and too one-sided" to use. Is she right?
Answer: No. For this research question the memoir is a strong primary source, because Marisol is asking about personal experience, and the writer lived it. Its age is not a weakness here, and its personal viewpoint is exactly the evidence she needs. Marisol should still check the memoir's factual details, such as dates and events, against a separate historical source.
This question targets the most common misunderstanding in the lesson: treating "old" and "one-sided" as automatic disqualifiers. Currency matters for topics that change, such as technology or health guidance, but a first-hand account of a 1963 event does not become less accurate as time passes. Likewise, a personal perspective is the point of a memoir — Marisol is not asking for a neutral overview, she is asking what the experience was like. What she still owes her reader is verification of checkable facts, which is the fourth question at work.
FAQ
- Can I use Wikipedia for a school research project?
- Use it the way researchers do: as a starting point, not as a source you cite. It is genuinely useful for getting the basic story, learning key terms, and spotting the names of important people and studies. Then scroll to the references at the bottom and follow those citations to the original reports, articles, and documents. Those originals are what you quote and cite. Check your teacher's requirements too, since some assignments have specific rules about reference works.
- Does a web address ending in .org or .edu mean the source is reliable?
- No. Anyone can register a .org address, and .org sites include advocacy groups with strong positions they want you to adopt. An .edu address usually belongs to a school, but it may host a student's personal page rather than reviewed research. The ending is a hint, not a verdict. Keep asking who wrote it, when, why, and whether the claims can be checked elsewhere — those four answers are worth far more than the last three letters of a web address.
- What should I do when two credible sources contradict each other?
- Do not silently pick the one you prefer. First, look for a reason for the disagreement: different dates, different places studied, different definitions, or different sample sizes. Often both are right about different situations. Then say so in your writing. Naming the disagreement and explaining which source is better documented shows stronger research thinking than pretending everything agrees.
- How many sources do I need before a claim counts as verified?
- There is no magic number, but one independent confirmation is the realistic goal for each important claim in your paper. Quality beats quantity: two genuinely independent, well-documented sources are worth more than eight pages that copied one another. Save your hardest checking for the claims your argument depends on most.
Learn this with a teacher, not a page
The Crimsora tutor teaches Evaluating Sources live — explaining on a whiteboard, asking you questions, and adapting to where you get stuck.