1. A thesis statement:  Is the main idea that you are trying to convey in your work.  States plainly what you are trying to persuade your reader to believe.  You make an ASSERTION you intend to support.  Assertion: (n) A confident and forceful statement of fact or belief

2. Example of a Fact “The number of cases of skin cancer per thousand U.S. citizens has increased steadily since the 1920s.”  This could not be a thesis unless you were presenting a scientific essay on skin cancer rates.

3. Sample of a thesis statement: “That rates of skin cancer have increased steadily since the 1920s reveals the danger of the American obsession with getting a ‘healthy’ tan.”  This is a thesis because it requires argument and support.

4. Alternative Thesis Statements  “The increase in the rate of skin cancer since the 1920s derives more from Americans’ longer average lifespan than from the popularity of tanning.”  “The thinning of the ozone layer has potentially devastating long-term effects on the public health, as shown by the increase in the rate of skin cancer.”