In simple terms
A friendly intro before the formal notes — no formulas yet.
The Detective's Toolkit: Building Your EE Case
Your Extended Essay is like a complex investigation. Your success depends not just on the final conclusion, but on the quality of your evidence (sources) and the rigour of your techniques (methods). This lesson teaches you how to be a master detective, building an undeniable case to answer your research question.
Imagine you are a detective investigating a crime. You wouldn't just grab the first 'clue' you see. You would systematically collect different types of evidence—fingerprints (primary sources), witness testimonies (interviews/primary), and police reports (secondary sources). You'd use specific forensic techniques (research methods) and you would critically question the reliability of each witness and piece of evidence before presenting your final, convincing case in court (your essay's argument). Your EE requires the same meticulous approach.
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Define Your Case (RQ): Conduct preliminary reading to find a feasible and focused Research Question. Your RQ dictates the kinds of 'evidence' you'll need.
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Choose Your Toolkit (Methodology): Select the specific research methods (e.g., textual analysis, statistical comparison, historical inquiry) that will best help you analyse your evidence and answer your RQ. You must justify these choices.
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Interrogate Your Evidence (Source Evaluation): For every source, ask: Who created this? Why? What are its strengths for my investigation? What are its blind spots or biases? This is your critical thinking in action.
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Construct Your Argument (Synthesis): Don't just present a list of clues. Weave your evaluated evidence together to tell a story and build a single, powerful argument that directly answers your initial question.
Explore the concept
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Full topic notes
Formal explanation with the rigour you need for the exam.
Primary vs. Secondary Sources: The Building Blocks of Your Research
The first step in effective research is understanding the nature of your evidence. The distinction between primary and secondary sources is not just a definition to be memorised; it is a concept that shapes your entire research methodology. Your ability to select and integrate both types appropriately is a hallmark of sophisticated academic work.
Primary Sources are the raw materials of your research. They are original, unfiltered, and provide a direct window into your topic. For a Literature EE, the novel or poem is primary. For History, a letter or government decree is primary. For Biology, your own experimental data is primary.
Secondary Sources are works of analysis, interpretation, or synthesis. They are created after the fact and engage with primary sources. For a Literature EE, a critical essay about the novel is secondary. For History, a historian's book analysing the letters and decrees is secondary.
The Distinction is Contextual: A historian's book is a secondary source for an EE on the French Revolution. However, if your EE's research question is 'To what extent did Marxist historians in the 1960s shape the popular understanding of the French Revolution?', that same book becomes a primary source, as it is the object of your study.
A High-Scoring EE typically demonstrates a masterful interplay between primary and secondary sources. It uses secondary sources (e.g., scholarly debate) to frame the inquiry and provide context, but its core argument is built upon the student's own original analysis of primary source evidence.
Defining Your Methodology: Justifying Your Approach
Criterion A requires you to not only have a clear focus and method, but to communicate them effectively. 'Method' is more than just 'I read some books'. It is the systematic process you design to answer your research question. Your methodology is your justification for this process. In your introduction, you must explicitly state and justify your chosen approach.
Subject-Specific Methodologies: A Physics EE might use an experimental methodology. A Visual Arts EE might use a comparative visual analysis methodology. A Global Politics EE might employ a case study methodology. You must use the correct terminology for your discipline.
Justification is Key: Why did you choose a case study of two countries and not three? Why did you focus on close reading of three poems instead of a statistical analysis of an entire anthology? Your justification should link your method directly to the scope and demands of your research question.
Example Justification (Literature): 'To investigate the theme of memory in Virginia Woolf's Mrs Dalloway, this essay will employ a methodology of close reading, focusing on narrative perspective and stream of consciousness. This approach is most appropriate as it allows for a detailed analysis of the textual mechanics through which Woolf constructs her characters' inner worlds, a central component of the research question.'
Document Your Journey: Use the RPPF (Reflections on Planning and Progress Form) to document your thinking. If you changed your methodology part-way through, explain why. This demonstrates intellectual engagement and is valued by examiners.
In the introduction of your EE, dedicate a short paragraph to outlining your methodology. State the approach you have taken (e.g., 'This essay will adopt a historical-comparative methodology...') and briefly explain why it is the most effective way to answer your specific research question. This immediately signals to the examiner that you are meeting the top bands of Criterion A.
Criterion C in Action: Synthesis and Critical Evaluation
The highest marks for Criterion C are reserved for students who move beyond summarising sources and instead engage them in a critical dialogue. Your voice as the researcher should be central, orchestrating the evidence to build your unique argument. This involves two key skills: evaluation and synthesis.
Evaluation: This means assessing the credibility and utility of your sources within the body of your essay. Don't just list limitations in a footnote. Explain how a source's bias, scope, or date of publication affects the evidence it presents and how you are accounting for that in your analysis.
Synthesis: This is the art of weaving together multiple sources to make a single point. Instead of 'Source A says this. Source B says that,' aim for 'While Source A establishes the economic context, Source B complicates this by introducing social factors, suggesting that the primary driver was in fact a combination of both...'
Place Sources in Conversation: Show how your sources agree, disagree, build upon, or refute one another. Use this scholarly conversation to create a space for your own argument to emerge.
Avoid 'Source-Dumping': A low-scoring essay often has long paragraphs that are simply paraphrases of a single source. A high-scoring essay will have paragraphs that draw on multiple sources to support a single, clear topic sentence that is in the student's own voice.
Academic Honesty and Presentation (Criterion D)
Your research process must be transparent and honest. Criterion D (Presentation) assesses, in part, the formal elements that underpin academic integrity, such as your bibliography and citations. A consistent and accurate referencing style is not a minor detail; it is a fundamental requirement that demonstrates your respect for the scholarly work you have built upon.
Choose One Style and Stick to It: Whether it's MLA, APA, Chicago, or another recognised style, consistency is paramount. Check the preferred style for your subject group.
Cite Everything: Any idea, quotation, statistic, or piece of information that did not originate in your own mind must be cited. This includes paraphrased ideas.
Bibliography vs. Works Cited: A bibliography should include all sources cited in the essay. Do not include sources you consulted but did not end up using in the final text. The bibliography is not included in the final word count.
Formatting Matters: Pay close attention to details like page numbers, headers, and the overall layout. A professionally presented essay suggests a professional and rigorous research process.
Use a reference management tool like Zotero, Mendeley, or even built-in functions in Microsoft Word from the very beginning of your research. Manually creating a bibliography at the end is stressful and prone to errors. Get into the habit of adding a source to your manager and making a brief note on it the moment you decide it's useful.
Worked examples
See the formulas applied — reveal one step at a time, like the exam.
Sample paragraph from a History EE on the causes of the 1926 General Strike in the UK, demonstrating critical source evaluation.
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While the official government report published in 1926, The Industrial Crisis, attributes the strike primarily to 'revolutionary agitation' by a minority of union leaders, the source's value is limited by its clear political purpose. As a document produced by the incumbent Conservative government, its origin dictates a narrative that absolves ministers of responsibility and delegitimises the strikers' grievances. Its purpose was to reassure the public and justify the government's firm response. A more nuanced perspective is found in the private diaries of A.J. Cook, a key union leader. Cook's entries from 1925 reveal deep-seated concerns about miners' wage cuts and working conditions, portraying the strike not as a revolutionary plot, but as a desperate last resort. Although Cook's account has its own limitations—namely, a natural bias towards his own organisation's position—its value lies in providing an authentic, contemporary voice of the miners' leadership, a perspective entirely absent from the official government narrative. By synthesising these two opposing primary sources, it becomes clear that...
Sample paragraph from a Literature EE on F. Scott Fitzgerald's The Great Gatsby, demonstrating synthesis of critical sources.
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The decline of the American Dream is a central theme, yet critics are divided on its cause. For Marxist critics like Marius Bewley, Gatsby's failure is a direct result of a class-based society where 'Gatsby's dream is not an 'escape' from, but a capitulation to, the very materialism that corrupts it.' Bewley's focus on economic determinism, however, arguably overlooks the more personal, psychological dimensions of Gatsby's tragedy. A complementary perspective is offered by Lois Tyson, who applies a psychoanalytic lens to argue that Gatsby's obsession with Daisy represents a 'fixation on an unobtainable maternal figure.' Synthesising these views, it becomes apparent that Gatsby's dream is not defeated by social barriers alone, but by the inherently flawed and regressive nature of the dream itself. It is a dream that is simultaneously a product of a corrupting materialist society (as Bewley argues) and a manifestation of an impossible personal desire (as Tyson suggests), making his failure an inevitability rooted in both societal and psychological structures.
How it all connects
The big idea sits in the middle — tap a linked idea to explore the link.
Tap a linked idea to see how it connects back to the main topic — that connection is what examiners reward.
Glossary
Try to recall each definition before you reveal it.
Quick check
Answer in your head first — then tap to check. No pressure.
Revision flashcards
Flip the card. Test yourself before the exam.
Primary Source
A first-hand account or raw data created at the time of an event, or by an author/artist being studied. Examples: a poem, a diary, a lab report, a survey's raw data, an original artwork.
Key takeaways
Review these before you close the topic — retrieval beats re-reading.
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Primary Sources are the raw materials of your research. They are original, unfiltered, and provide a direct window into your topic. For a Literature EE, the novel or poem is primary. For History, a letter or government decree is primary. For Biology, your own experimental data is primary.
- ✓
Secondary Sources are works of analysis, interpretation, or synthesis. They are created after the fact and engage with primary sources. For a Literature EE, a critical essay about the novel is secondary. For History, a historian's book analysing the letters and decrees is secondary.
- ✓
The Distinction is Contextual: A historian's book is a secondary source for an EE on the French Revolution. However, if your EE's research question is 'To what extent did Marxist historians in the 1960s shape the popular understanding of the French Revolution?', that same book becomes a primary source, as it is the object of your study.
- ✓
A High-Scoring EE typically demonstrates a masterful interplay between primary and secondary sources. It uses secondary sources (e.g., scholarly debate) to frame the inquiry and provide context, but its core argument is built upon the student's own original analysis of primary source evidence.
Practice — then mark it
The whole point: a real Cambridge question, marked mark-by-mark.
Test Your Knowledge on Research Methods
Test Your Knowledge on Research Methods
Extra simulations & links
PhET, GeoGebra and other curated tools — open in a new tab.
Frequently asked
Checkpoint
One marked question is worth ten re-reads — close the loop before you move on.
Reading it isn’t knowing it — prove it.
Before you move on: do Test Your Knowledge on Research Methods on paper, snap a photo, and get examiner-style feedback on exactly where you win and lose marks.