Don't be fooled by the fact that a thesis statement is only one sentence long. Your entire essay is based upon this crucial sentence. The key to a successful thesis statement is to respond directly to the prompt, be specific, and get straight to the point. Often, your initial thesis statement will develop and grow more precise after you have written the essay.

Make it Debatable

A thesis statement is not a fact. It is a statement that requires elaboration and support and can prompt a discussion. If the statement is self-evident, then it is not an effective thesis statement. For example, the following statement is not debatable and is therefore a poor thesis: "Every day people without cars take public transportation." This sentence is a fact; it does not argue anything and is not making a point that can be discussed. A possible thesis statement based on this topic can be "The city should provide more frequent bus and train service for the countless citizens who cannot afford to own a vehicle."

Be Specific

A common challenge for writing a thesis statement is making it sufficiently narrow and specific. The wording in the statement should not be too general; words like "good," "bad," "change" and "affect" can be too subjective or neutral to convey a specific meaning. Also, the content of the statement should not be too broad. Justus Liebig University warns writers to avoid writing thesis statements that are vague, underdeveloped and too broad to be thoroughly covered in a single essay. For example, the scope of the statement "Violence is rising across the globe" is too wide. An overly broad statement that ignores important nuances and details also runs the risk of being untrue and leaving the reader with questions.

Write a Complete Sentence

A thesis statement should never be written in question form; if you find that you are writing a question, then most likely the actual thesis statement is the response to that question. For example, the following is a poor thesis statement: "Why do so many people suffer from obesity?" However, if you respond to this question, you can create an effective and complete thesis statement: "As a result of the rising costs of healthy food and a decrease in physical activity, the rate of obesity is rising in the U.S."

Just Say It

Your thesis statement should get straight to the point. Rather than making an announcement, just make the point. For example, instead of writing "I'm going to write about how curfews are good," write "Curfews are good for teenagers because they provide a stable structure." Also, avoid words and phrases that serve only to set up the statement, such as "in my opinion" and "I believe" -- these are just filler and don't add any meaningful content to the essay.