Start with the simple equation:
THESIS = subject + assertion

A strong thesis essential to a successful essay. Without it your essay will lack focus-it'll seem to have little direction. A clear thesis, on the other hand, helps you and the reader stay on track. It's often called the "main idea" or the "controlling idea" because it controls the content of the essay.

POINT TO REMEMBER. A thesis names your general subject and makes an assertion about that subject. It states the topic and the point you want to make about that topic. A strong thesis, therefore, is both general and explicit.

Example

I believe in heroes-that they still exist-but they aren't like celebrities; in fact, heroes differ greatly from celebrities in that their actions are meaningful rather than frivolous, selfless rather than self-aggrandizing, and courageous rather than brazen.

Why is this a good thesis?
First, the subject is named. (heroes )
Next, the assertion is clear-it is both general and explicit. (…they exist but are unlike celebrities in that their actions are meaningful, selfless, and courageous…)

POINT TO REMEMBER: The thesis is a general statement with explicit terms. In the above example, three qualities are named (made explicit), but they are all general enough to need further explanation (they suggest how the writer needs to develop the paper).

POINT TO REMEMBER: The thesis is a complete, grammatical sentence which is smoothly integrated into the essay. It usually appears somewhere in the introduction, but may be repeated throughout the essay in slightly different words. When you use explicit terms, you may find it helpful to remember to use parallel sentence structure.

Which of the following thesis statements do you think are strong? Which ones weak?

What are your reasons?

The ideal teacher is knowledgeable about the subject matter and good at finding ways to communicate that knowledge.

The ideal teacher knows a lot.

Three passions I have lived for are music, art, and literature.

Three passions I have lived for are music, painting, and to write stories.

These thesis statements are all strong, and they all suggest that an expressive essay will follow.

• I hope college will improve my general knowledge and my chances of getting a good job.
• Moving to St. Louis has provided me with the opportunity to pursue my career, make new friends, and see new places.
• The ideal student has an eager, independent curiosity and self-determination to meet difficult challenges.
• The ideal guitar shop is well stocked and has a friendly, inviting atmosphere.
• The ideal classroom is an open mind.