The thesis statement declares the main point or controlling idea of the entire essay. The thesis briefly answers the questions, "What is my opinion on subject X?" and "What am I going to argue/illustrate in this essay?"
1. A good thesis states the writer's clearly defined opinion on some subject. You must tell your reader what you think. Don't dodge the issue; present your opinion specifically and precisely. However, don't just make your thesis an announcement of your subject matter or a description of your intentions.
Poor: The subject of this theme is my experience with a pet boa constrictor. [This is an announcement of the subject, not a thesis.]
Poor: I'm going to discuss boa constrictors as pets. [This is a statement of intention, but not a thesis.]
Better: Boa constrictors do not make healthy indoor pets. [The writer states an opinion that will be explained and defended in the essay.]
Better: My pet boa constrictor, Sir Pent, was a much better bodyguard than my dog, Fang. [The writer states an opinion that will be explained and illustrated in the essay.]
2. A good thesis asserts one main idea. Many essays get into trouble because the writer tries to explain two different large issues in one essay. Pick one main idea and explain it in convincing detail.
Poor: High school athletes shouldn't have to maintain a certain grade-point average to participate in school sports, and the value of sports is often worth the lower academic average. [This essay moves in two different directions.]
Better: High school athletes shouldn't have to maintain a certain grade-point average to participate in school sports. [This essay will focus on one issue: reasons why a particular average shouldn't be required.]
3. A good thesis has something worthwhile to say. Some thesis statements are boring and predictable from the start ("Dogs have always been man's best friends."). Even if you are asked to write about yourself or your own experiences, you can usually universalize the essay's thesis so your readers can also identify with, or learn something about, the general subject.
Poor: The four children in my family have completely different personalities. [This statement may be true, but would anyone but the children's parents really be fascinated with this essay topic?]
Better: Birth order can influence children's personalities in startling ways. [The writer is wiser to offer this controversial statement, which is of more interest to readers than the one above; the writer can illustrate her claims with examples from her family, and from other families, if she wishes.
Also, don't merely state a fact. A thesis is an assertion of opinion that leads to discussion; don't select an idea that is self-evident or dead-ended.
Poor: Child abuse is a terrible problem in our country. [Yes, of course; who wouldn't agree that child abuse is terrible?]
Better: Child abuse laws in this state are too lenient for repeat offenders. [This thesis will lead to a discussion in which supporting arguments and evidence will be presented.]
4. A good thesis is limited to fit the assignment. Your thesis should be focused enough to adequately explore and develop in one essay.
Poor: The parking permit system at this university should be completely revised. [An essay calling for revision of the parking permit system would probably involve discussion of permits for various kinds of students, faculty, administrators, staff, visitors, etc. Therefore, the thesis is probably too broad for a short essay.]
Better: Because of the complicated application process, the parking permit system at this university penalizes disabled students.
5. A good thesis is clearly stated in specific terms. A vague thesis will lead to vague, undeveloped, fuzzy writing. Try to avoid imprecise words ("interesting," "good"); use clear, direct, meaningful words. Also, don't clutter your thesis with expressions such as "in my opinion" or "in this essay I'll argue that ..."
Poor: My opinion is that the federal government should devote more money to solar energy research.
Better: The federal government should devote more money to solar energy research.
6. A good thesis is clearly located, often in the first or second paragraph.
Revise the following, thesis statements to make them more effective according to the criteria above.