Another option, if you are looking to purchase a book of poetry, I suggest Half Hours with the Best Poets (Barnes & Noble or Amazon)
This is a fantastic collection of poems, nearly all of my top poems are in this one book!
So the next poem is
The title is a link to the poem
I think we all had to read, memorize or paraphrase this poem in High School! Even though it was homework then I enjoyed it and I still enjoy it. There are many many ways to interpret O Captain! My Captain! but I prefer to read it as it is without any symbolism. It is only a few short lines but it tells a story of a successful voyage, and the homecoming and then tragedy. Quite a range of emotions and picture painted for so few words. This is definitely one of those classic poems that will remain one of the greats!