How to write an introduction:
How to write a thesis statement:
Now let's take a look at your most recent intro:
High school students are known for their "out of control behavior". <~~This is a vast generalization. =( You are saying that all high school students are out of control?
Communities are considering to adopt curfews for high school students.<~~Many towns and cities in this country already have curfews; they don't have to consider.
On the contrary, others think that it is up to the family and that not having curfews can possibly be a good thing. <~~This sentence doesn't make good sense. Also "can" and "possibly" mean the same thing; cut out redundancy.
Although it is important to restrict high school students, the communities should leave it up to the family. <~~Is this your thesis statement?
Hence, communities should not impose curfews on high school students. <~~If this is not your thesis statement, then delete it.