I. Introduction
- Hook: a surprising fact or a question the essay answers
- Define the topic and any key term
- Thesis: the topic + the 2–4 parts, causes or steps you will explain
Expository essay outline
An expository essay outline has an introduction that names the topic and the parts you will explain, one body paragraph per part (topic sentence, facts or examples, explanation), and a conclusion that pulls the parts together. It informs; it does not argue for a side.
Best for: Explain-how or explain-why prompts, informative essays and many standardised test tasks.
II. Part / cause / step 1
- Topic sentence
- Facts, examples or data (cited)
- Explanation in your own words
III. Part / cause / step 2
- Topic sentence
- Facts or examples (cited)
- Explanation
IV. Part / cause / step 3
- Topic sentence
- Facts or examples (cited)
- Explanation
V. Conclusion
- Restate the thesis
- Show how the parts connect
- Why understanding this matters
Worked example
Topic: How vaccines train the immune system
Thesis: Vaccines work in three stages: they show the immune system a harmless version of a germ, the body builds antibodies and memory cells, and those cells respond fast if the real germ appears.
Stage 1
- Antigen: weakened, inactivated or partial germ, or mRNA instructions.
- Source: CDC, "Understanding How Vaccines Work".
Stage 2
- B cells make antibodies; T cells help and attack infected cells.
Stage 3
- Memory cells allow a faster, stronger response later.
Square brackets mark where your own research goes. Never fill them with made-up sources.
Tips that change the grade
- Stay neutral
- Leave out "I think" and "should". If you find yourself arguing, you are writing an argumentative essay.
- Pick an organising pattern
- Process (steps), cause and effect, compare and contrast, classification or definition. Use one per essay.
- Define before you explain
- If the reader needs a term to follow paragraph 2, define it in the introduction.
Other outline templates
5-Paragraph Essay OutlinePersuasive Essay OutlineNarrative Essay OutlineResearch Paper OutlineCompare and Contrast Essay OutlineArgumentative Essay OutlineAll essay outline templates
Questions students ask
What are the types of expository essay?
Common ones are process (how to), cause and effect, compare and contrast, classification, definition and problem-solution.
Does an expository essay have a thesis?
Yes. It states what you will explain and how it is organised, rather than a position to defend.
Can I use "I" in an expository essay?
Usually not. Expository writing is impersonal and third person unless your teacher says otherwise.