How to write a strong thesis statement

What a thesis statement is, and what it is not

A thesis is the answer to the question your essay is asking. If the prompt asks whether schools should start later, the thesis says yes or no and why. If the prompt asks how a character changes, the thesis names the change and what causes it. Every paragraph that follows should help prove that one sentence.

A thesis is not a topic, a fact, or an announcement. "This essay is about social media" names a topic. "Most teenagers use social media" is a fact nobody would argue with. "In this essay I will discuss social media" announces that an essay exists. None of them gives the reader a position to test.

The test is simple: could a thoughtful person disagree with your sentence, or at least ask "how do you know?" If yes, you have a claim worth proving. If no, you have a starting point, not a thesis.

Weak and strong thesis statements compared

Each pair below starts with a weak version and then shows a stronger one. Notice that the strong versions are specific, take a side or make an interpretation, and suggest the reasons that will follow.

• Weak: "Video games have good and bad effects." Strong: "Schools should use strategy video games in math class because they give students instant feedback and make them practise the same skill many times without boredom."
• Weak: "Romeo and Juliet is about love." Strong: "In Romeo and Juliet, Shakespeare shows that haste, more than fate, destroys the lovers, since nearly every disaster follows a decision made in a rush."
• Weak: "Recycling is important." Strong: "Our town should charge for household trash by the bag, because paying per bag gives families a direct reason to recycle and costs the town less than a new landfill."
• Weak: "Frankenstein is a book by Mary Shelley." Strong: "In Frankenstein, Victor is more monstrous than his creature, because he abandons the being he made and then lets others suffer for its crimes."
• Weak: "I will talk about the causes of the Great Depression." Strong (informative): "The Great Depression deepened after 1929 because thousands of banks failed, spending collapsed, and world trade shrank."

Three steps to write a thesis

Most students find it easier to build a thesis in stages than to write a perfect sentence first.

• Turn the prompt into a question. "Discuss the role of the setting in The Most Dangerous Game" becomes "How does the setting shape what happens in The Most Dangerous Game?"
• Write a one-sentence answer. "The island makes Rainsford's survival harder." This is your working claim.
• Add the because. "The island's jungle, swamp and cliffs turn Rainsford from hunter into hunted, forcing him to use the same tricks he once dismissed in animals." Now the reader knows the claim and the reasons, which become your body paragraphs.

Thesis statements for different kinds of essays

The shape of a thesis changes with the essay's purpose.

An argument essay needs a clear position on a debatable issue: "Cities should replace some street parking with protected bike lanes, because they reduce injuries and make short trips cheaper." Stronger argument theses also leave room to answer the other side, for example by starting with "Although bike lanes remove parking spaces, ...".

A literary analysis needs an interpretation of a text, not a plot summary: "In A Christmas Carol, Dickens uses the three spirits to show that a person changes only after seeing how his choices affect other people." The claim is about how and why the author does something.

An informative or explanatory essay does not argue for a side, but its thesis still makes a focused point and maps the essay: "Volcanoes form in three main settings: where plates pull apart, where one plate sinks under another, and over hot spots."

Where the thesis goes and how long it should be

In most school essays the thesis is the last sentence or two of the introduction. The introduction opens with a hook and some background, narrows to the issue, and then lands on the thesis, so the reader moves straight from your claim into the first body paragraph.

One sentence is usual for a five-paragraph essay. Longer research papers sometimes need two sentences: one for the claim and one that maps the reasons. If your thesis runs past about 40 words, it is probably trying to do too much; cut the details and save them for the body.

It is normal for a thesis to change while you write. If your evidence leads somewhere different from your first claim, revise the thesis to match what you actually proved, then reread the introduction.

Common thesis mistakes and how to fix them

Teachers mark the same problems again and again. Each has a quick repair:

• Too broad: "Technology has changed the world." Narrow the subject, place and time: "Smartphones have changed how teenagers in the United States get news."
• Just a fact: "Romeo and Juliet is set in Verona." It is true, so there is nothing to prove. Ask what is interesting about the fact: "The feud in Verona's streets makes private love impossible to keep private."
• Announcing: "This essay will explain..." Delete the announcement and state the point itself.
• A question: "Should homework be banned?" A question can hook a reader, but the thesis is your answer to it.
• Two unrelated claims joined by "and": pick the one you can prove best, or show how they connect.
• Vague words: "good", "bad", "interesting", "important". Replace them with what you mean: "unfair to students without internet at home".

How to check and practise your thesis

Read your thesis aloud and ask four questions: Does it answer the prompt? Could someone disagree, or ask how I know? Is it specific enough to prove in the length I have? Does each body paragraph prove part of it? A no to any question shows you what to revise.

A useful practice routine is to take one prompt and write three different theses for it, each taking a different position. Then choose the one with the best evidence behind it. Another is the "so what" test: after reading your thesis, ask "so what?" If your next sentence answers that, consider folding it into the thesis.

Comparing your sentence with the strong examples above, or with model essays your teacher shares, helps you see the difference between a topic and a claim.