This list is all over the place -- Zora Neale Hurston's moving Their Eyes Were Watching God to Geoffrey Chaucer's rollicking Canterbury Tales. I've read 74 of the books, and can easily see picking up the rest. For the time-crunched, there's a short list that skews toward the more traditional lit-class offerings. For the not-so-time-crunched, there's a list of historical texts and recommended poetry readings.
I was pleasantly surprised to see Gwendolyn Brooks' "We Real Cool," which rattled around my head for days the first time I read it. It was one of my favorite accidental discoveries in my 11th-grade English book. The other was Edgar Lee Masters' Spoon River Anthology, and Louise Smith's poem, followed by Herbert Marshall's.
We never read these poems for class. If I hadn't been a speed-reader and easily bored as we plowed through the fourth day of discussing "A Rose for Miss Emily," I'd have never furtively flipped around my book and found these wonderful things.