Central Idea

What is a Classification Essay?

A classification essay is a formal essay format meant to showcase your ability to categorize and generalize information.

When you classify something, you’re organizing it based on what you know about it. Classification essays aim to help the reader understand the topic more thoroughly and come to agree with your criteria for categorization.

For example, you could categorize the presidents of the United States according to those that had health issues while in office, and those that did not. For those that had health issues while in office, you could subdivide them by what type of health concerns they experienced (i.e., heart condition, cancer, psychological disorders, etc.). Your criteria for categorization is US presidents who experienced health concerns while in office, and what type of issues they had. This could communicate something interesting about the effects of the presidency on the body, or any other number of messages (depending on the findings).

What is the Central Idea in a Classification Essay?

The central idea, or thesis, of a classification essay is one part a statement on how you classify things and one part your justification for how you classify those things.

The main idea should name what group of people or things you intend to classify and should describe the premise for classification, which is also called a classification principle. This means explaining what the items all have in common to place them in the same category.

The difference between a central idea and a theme is that central ideas are typically the substance of informative texts, such as essays. Themes are the message behind a literary text, like a poem or novel.

A Synonym for the Central Idea

The central idea of a classification essay—or any essay—is also known as the thesis. Both terms refer to the point of your essay.

There may not be much to argue about in a classification essay, but your thesis should still contain an opinion about the topic in some shape or form. Your opinion is present in your rationale for how you categorize the subtopics. You might believe that there are only X number of ways to do something. Or you might argue that A, B, and C are the best options for topic Y. Other people might disagree and think there are more than X number of ways to do something. Some might argue that D, E, and F are actually the best options for topic Y.

Regardless of your topic and opinion, your classification essay needs a central idea to make it meaningful.

Examples of Central Ideas in Classification Essays

Here are a few examples of thesis statements for classification essays. After each example, there is a breakdown of how the central idea would function in a full essay.

The central idea of this thesis statement is that kids can also contribute to environmental protection efforts. The essay will develop that idea with examples from the categories (eliminating single-use packaging, conserving water, and playing outside).

The central idea of this thesis is that these three National Holidays have positively impacted culture in the US. Others might argue that these Holidays have had unintended negative effects, but this classification essay can explore the ways each of these Holidays has contributed something positive.

Purpose of a Central Idea in Classification Essays

The central idea of a classification essay is not simply a declaration of how many types of something there are. For example, the statement “There are two types of sports you can play: team sports and individual sports” does not contain a central idea. While this might be a true statement, it doesn’t leave much room for the development of the topic into a full essay. Every essay must have a thesis statement that contains a unique central idea.

A thesis has a few basic roles to fulfill, regardless of the type of essay. A thesis statement should:

• Establish an expectation for what the essay will discuss.

• Express your central idea (or “the point” of the essay).

• Provide structure for the essay with the main points of development.

The central idea is the heart of a thesis statement. It is the place where you present your argument and the information you plan to use to prove your claim is true.

The goal of a classification essay is to say something meaningful about how parts of the topic are related to the whole, or how the whole relates to its parts. The central idea includes this message.

Fig. 2 - The central idea of a classification essay provides an image of the whole topic by way of division.

In addition to the general purposes of a thesis statement (listed above), a thesis statement of a classification essay will also:

• Explicitly state the main topic and the categories (subtopics).

• Explain the rationale for the categorization (the way you arranged the subtopics).

Formulation of the Central Idea in Classification Essays

The thesis of a classification essay looks like this:

Main topic + subtopics + rationale for the subtopics = thesis

Coming up with a central idea or thesis statement is the last element of the prewriting process. To write a classification essay, you first need to decide how you want to group your like-items based on a classification principle.

If you don’t know how you want to divide your topic, ask yourself the following questions:

• What do I know about this topic?
• Does it divide easily into categories (i.e., subtopics)?
• What is my unique perspective on the topic?
• What meaning can I contribute to the topic with my classification?

Next, decide what criteria are important enough to your topic to discuss at length.

For example, your topic might be academic stress. You might decide to talk about tips for mitigating the stress many students experience around midterm and finals time. Now you must decide on your classification principle (i.e., the way you’re going to divide up the ways to de-stress during finals). You can develop a classification principle through research and prewriting exercises.

During prewriting for a classification essay, be sure to look for parts of the topic that you feel you can communicate something important through your classifications.

Referring back to the stress example, after your research and prewriting exercises, you might come to the conclusion there are several ways for students to manage stress. You find they tend to fall into one of three basic categories: personal care, periodic study breaks, and meditation. Use your classification principle—things students can do to de-stress—to come up with more content to put in your categories.

Now that you have your subtopics, or categories of classification, prepare to explain your rationale for this division. In the case of academic stress management, your rationale might be that these are the only things within a student’s control to manage stress. So, your central idea is that students should focus on controlling what they can and letting go of everything else to diminish academic stress.

A decent thesis statement might be:

In this way, you're able to make a comment on the topic of academic stress by categorizing strategies for mitigating the effects of stress.