I'm assuming you mean the poem "We Real Cool" by Gwendolyn Brooks.
The poem itself is quite short, which makes it seem odd to think of the poem in terms of plot or events. However, upon closer reading, a plot does emerge.
At the beginning of the poem we have our main character(s), who believes he is "real cool." He plays pool with his friends and believes he is highly regarded by others. But this is the beginning of the story, and things quickly change. The character goes from playing pool to "leaving school." Our character is embarking on a series of poor choices which will have serious consequences. From leaving school the character moves on to staying out late, drinking, sinning, singing, and then, the last event of the story, dying.
In her poetry, Gwendolyn Brooks strives to "feature people and their concerns—their troubles as well as their joys." Her brief poem, "We Real Cool"—
We real cool. We
Left school. We
Lurk late. We
Strike straight. We
Sing sin. We
Thin gin. We
Jazz June. We
—demonstrates how Brooks makes use of short sentences, dialect, and sound devices that mimic jazz riffs (brief musical phrases repeated over changing melodies) in order to suggest the language of the youths and their limited view of the world. They quit school and hang out until late at night, drinking, loitering, and playing pool. They may also be engaged in illicit activities, as suggested by the phrases "Sing sin" and "Thin gin."
Interestingly, Brooks's use of dialect leaves readers with only those words that will most greatly affect them. Also, sound devices in the poem are meant to touch the emotions. For instance, the sound device of alliteration in phrases such as "Lurk late," "Strike straight," and "Sing sin" suggests the speed and lack of forethought given to the actions of the youths because they feel that they are "cool" and do not worry about the repercussions of their actions.
Clearly, Brooks's poem is an instructional one, as the youths' actions lead to the abrupt end that is expressed in the short phrase "Die soon." This sudden and mortal end teaches the reader that a sequence of choices like those displayed by the youths in the poem usually leads to some form of death.