Thesis Statements - The Writing Center
Examples of a good thesis sentence includes a summary of the writer's arguments about the subject of the written piece. A good thesis sentence answers a question that the body of the paper answers and explains in greater detail. The sentence should provide the reader with an overview of what the writer is trying to convey in the rest of the paper.
Purdue OWL: Establishing Arguments
Put another way, a good thesis sentence will inspire (rather than quiet) other points of view. One might argue that America is violent because of its violent entertainment industry. Or because of the proliferation of guns. Or because of the disintegration of the family. In short, if your thesis is positing something that no one can (or would wish to) argue with, then it's not a good thesis.
We also know that not all students can write good thesis sentences, and it is one of the reasons why they get low grades on their papers. If you are one of them, if nothing helps you including sample thesis sentences and instructions from your teachers, then let us try to explain you the essentials of creating a good thesis sentence.