There are two general types of cover letters. It is important to pay close attention to these different types because the type of cover letter you are planning to write will (or should) have an impact on the content of the letter. Before you write a cover letter you must ask yourself if you are writing for a specific purpose or are you planning to send it as part of an unsolicited application.
Letters for Specific Employment Openings: This category includes replies to job postings listed on the US School Jobs Network or traditional classified ads in city, town and neighbourhood newspapers; responses to listings from college career Centers, school/district/union bulletin boards, and other sources; and applications for definite job openings that you hear through word-of-mouth. See Sample Cover Letters for more information.
Unsolicited letters: This category includes any letters you write to inquire about possible job openings or internship opportunities in organizations you've targeted through your research and networking. See Sample Cover Letters for more information.
Composition of Cover Letters
The structure of a cover letter contains four steps. Within each of these sections an applicant will reveal themselves and their intentions to the employer. Be clear and to the point. You want to focus the attention of the employer on your best attributes and most relevant qualifications for the job you are applying for, as to consider you for an interview.
The opening paragraph: states your reason(s) for writing and the objective - the position for which you wish to be considered.
The pitch: The second paragraph provides some insight about you and should refer to your past accomplishments that are relevant to your objective (the employer hiring you for this position).
The why me? part: The third paragraph should summarize why you would be an asset to the prospective school or district. What are the benefits to the employer in hiring you?
The request for action: This section is often referred to as the closure, but that's a passive way of looking at it. Don't just think of it as the time to say "thank you and good-bye," but as the chance to request a next step, like an interview or phone conversation. The request for action is where you further clarify your objectives (you really want the job!)