The thesis statement is the “Pow!” of the opening argument of a case. Every persuasive written piece has the sense of a court case with the opening statement, evidence, and concluding statement.
The easy way to construct a thesis statement is to utilize the following phrase as “training wheels” to guide what you will say in your thesis: “In this essay I will prove . . .” In other words, the thesis statement states what you will bring evidence in to prove a persuasively written piece. For example, if you fill in the guide with “In this essay I will prove racism is wrong,” your thesis is: “Racism is wrong.” A thesis is a soapbox to stand on and one should kick off the training wheels once one understands what it is they are trying to say.
If a person is trying to write the classic five paragraph essay, s/he can add three pieces of evidence—one for each body paragraph—to the statement they have developed as the thing they are trying to prove. For example, “Racism is wrong because it often causes violence, hurts other people’s feelings, and leaves people out.” If I were reading this thesis at the end of an introductory paragraph, I would expect to read about the violence racism causes in the next paragraph, the third paragraph (second body paragraph) would be about how racism damages emotions, the fourth paragraph (third body paragraph) would be about how racism excludes people. The essay would then end in a concluding paragraph.