Sometimes when we write an essay we forget that we're speaking to someone (a reader). We also forget that the beginning of our essay is technically the first impression that we make on the reader, while the conclusion is our last chance to get the reader's attention. Rather than focusing on writing an essay that is simply "correct" (in terms of grammar, following your assignment requirements, etc.) good writers also consider whether or not they've left a lasting impression on their reader. Think about it: the movies you've seen and the books you've read, the ones that really stand out in your mind, probably had an intriguing opening and a compelling ending. Your essay topic may not be as exciting as your favorite movie, but that doesn't mean you can't make sure that your ideas stand out in the reader's mind.
The order of items above is the best order to present each part of the introduction: get the reader's attention, move toward the thesis statement, and then present the thesis statement. The thesis statement usually is most effective as just one sentence at the end of the introduction, so you should avoid presenting the thesis statement as the first sentence of the introduction and should avoid presenting the thesis statement in more than one sentence. (Information about thesis statements is presented on The Thesis Statement Web page.)
1 Historical review: Some topics are better understood if a brief historical review of the topic is presented to lead into the discussion of the moment. Such topics might include "a biographical sketch of a war hero," "an upcoming execution of a convicted criminal," or "drugs and the younger generation." Obviously there are many, many more topics that could be introduced by reviewing the history of the topic before the writer gets down to the nitty gritty of his paper. It is important that the historical review be brief so that it does not take over the paper.