Thesis Statements

On this page you learn about claims and writing thesis statements

The thesis statement is the most important sentence in an essay. It establishes the authors claim and a lays out a map of what the essay is going to contain and where to find it. A thesis statement in any high school level essay, is only one sentence long. If your thesis statement is more than a single sentence, it needs to be revised. A thesis statement longer than a single sentence is only appropriate for much larger research tasks and full length books.

What is the purpose of a thesis statement?

  • Focuses your ideas into one sentence

  • Present the argument of your paper (your claim)

  • Make a comment about your position in relation to the topic

  • Tell your reader what the paper is about (and what to expect from it)


“The Lord of the Rings trilogy is the best fantasy book to film adaptation ever made based upon critical reception, profit made, and impact on the film industry.”


Here, we have a thesis statement. This is a good thesis statement because...

  • It defines the subject of the essay, The Lord of the Rings trilogy film adaptations.

  • It establishes an opinion or stance on the subject, in this case, they are best film adaptations ever (a bold statement!)

  • It lays out what the three body paragraphs are going to be about. The first paragraph of the essay is going to be about how the critics responded to the film, the second paragraph about how much money it made, and the third paragraph will be about the films impact on the film industry.

Developing a Three-Prong Thesis Statement

A thesis is the most important sentence! It tells what your whole paper is about, and keeps you on track as you write. The thesis is the anchor of the whole paper, everything must connect back to your thesis statement and support it.

The formula for a three-prong thesis statement is:

Claim (what you are trying to prove) + Three supporting points = Three prong thesis

Your supporting points are in the same order that they will appear in the essay. In a single sentence you have stated your claim, how you will prove that claim, and provided a map of the essay. What a powerful sentence this truly is!

It can be tricky to get so much information into a single sentence, so you must be concise with how you write. Remember, the thesis is not explaining any details, only pointing out the points that you will use to prove your claim. Check out the example below.

This table is a great way to plan your thesis. On a piece of paper or in a document, create a table like the one pictured.

  • The claim is at the top, make sure your claim is concise and firm.

  • The supporting points are listed below, notice how they would also make great topic sentences!

  • Put the claim and the supporting claims together. Use a connecting word (explained below). Notice how in the example, the author made use of only the most important key words in the final thesis statement?

Use connecting words!

Use connecting words and phrases to link to your body paragraphs, such as:

  • by

  • due to

  • as a result of

  • demonstrated by

  • because

  • in order to


See the connecting words in action!

My school is the best school in the world due to point one, point two, and point three.

The iPhone is the best smartphone because point one, point two, and point three.


Five General Rules for Thesis Statements

Crafting an effective thesis is a very important step for writing an essay. Check your thesis using this five rules!

Rule 1

A thesis statement makes an assertion; it is not a simple statement, fact, or observation.


An assertion is a confident and forceful statement of fact or belief. Your thesis statement must have this present in order to be effective. However, it is not simply making an observation or stating a fact plainly. It must make an assertion. Consider the example below.

"Smoking is bad for your health."

There are a few key issues with this thesis statement, but most importantly, it is making a simple statement or observation without providing any reasoning. This is not a thesis because it is simply a fact. What this thesis needs to become effective, is to make an assertion. We can transform this simple statement into thesis statement by unpacking what "bad" means in this context:

"Smoking is detrimental to your health because it causes cancer, lung disease, and digestion problems."

This revised thesis is no longer stating a fact or observation, it is making a statement. Instead of using the very general word "bad," the author is being more precise with their meaning and using the word "detrimental." This revised sentence also has three supporting reasons (that are also the roadmap of the essay, see rule 4 below).

Rule 2

A thesis statement takes a stand. It does not make an announcement.

Your thesis needs to make a clear stand on the subject of the paper. Consider the thesis statement below, writing on the subject of English class:

"This paper is about English class and why it's so great."

This sentence is making an announcement that English is a good class (as we all know). There are a few issues with this thesis, but what we are focusing on here is that it is simply making announcement. It is announcing what the paper is about, but is not taking a stand on its subject, English class.

"English classes are the most exciting courses of a student's day because reading is enjoyable, essays are fun, and critical analysis is entertaining."

This thesis has been revised to take a stand on English classes, and included three reasons to support that statement. This thesis is no long making a simple announcement, it is taking a stand on the subject.

Rule 3

A thesis statement narrows the topic and is specific.

Your thesis statement needs to narrow the topic or subject, and be specific about what is being written about. The first two rules of thesis statements should eliminate your thesis from being too general, but it is important to check your thesis and make sure you have narrowed the topic down and are being very specific about your subject.

"Reading is good for people because it makes them think, imagine, and make things."

At first glance, this seems to be an okay thesis, but it needs to more specific about what they are writing about. Check out the revision below:

"Reading fiction is good for teenagers because it encourages critical thinking, inspires the imagination, and motivates them to create other works of art."

This revised thesis is significantly more specific. In the revised version, instead of using the general term "people," the author narrowed their topic to "teenagers." The three supporting reasons were also made more specific. The first, "think," is general. There are many types of thinking. They author narrowed their subject further by specifying what kind of thinking they are actually writing about.

Rule 4

A thesis statement maps out the content that is to follow.

In all the examples above, you will see one common element in the revised thesis statements; they each have a list of three things at the end of the sentence. These are the supports for the claim being made, and they are listed in the order in which they will appear in the essay. Look at the anchor thesis below for help on building this!

It also makes use of what is called, the Oxford Comma. You can learn all about this specific comma usage over in the grammar section of this website.