Write A well-told story and include the following;
A vivid presentation of places and people
An indication of the event’s significance.

This can be treated as the thesis of the essay. A memoir’s significance doesn’t have to be stated directly, but it should be clear from how you tell the story. And if it IS stated directly, it doesn’t need to be at the beginning–though there should be SOME indication of it at the beginning.
There is not a minimal paragraph requirement, but a general rule of thumb in this class is that your essays should be at least 3-5 pages long. This one may be longer–and you may have many more paragraphs since each new line of dialogue (each time the speaker changes) is its own separate paragraph.

Careful attention to detail is important–typos, spelling, punctuation, etc. Grammatically correct sentences are important. All of these make your essay readable for the reader.