When I was young, I used to walk to and from school, and I often walked home for lunch - about six miles, all told. I used to keep myself amused by reciting poetry as I strolled along (I know, I was a strange kid). Mostly, it would be long poems from Keats or Robert W. Service.
Then, one year at school, we covered Matthew Arnold, including his longer works "The Scholar Gypsy", "The Forsaken Merman" and "The Voyage of St Brandon". I loved them and they became firm walking favorites; I had them off pat pretty quickly. Towards the end of the school year when they tested us in English, I wrote out whole chunks of Arnold on the answer paper (word and punctuation perfect) and referred back to them when answering the questions. I thought it was a pretty neat thing to do, I didn't realize it would lead to problems.
When the test papers had all been marked, my English teacher read out the results in class - mine wasn't included. "Please sir, I think you've missed me out." But no, he hadn't - he was saving me 'til last.
"We haven't awarded you a mark, boy. I think you know the reason why. You seem to have a quite remarkable grasp of Arnold's work. Perhaps you'd like to stand up in front of the class and demonstrate your immense knowledge by reciting one of his poems - "The Voyage of St Brandon", for example?"
Oh my god - he thought I'd been cheating! What could I do? I stood up and started reciting - I got about half way through the fourth stanza before he stopped me. I'd vindicated myself, for sure, but I'd also guaranteed that my classmates would henceforward regard me as some kind of freak, and I'd earned the lasting enmity of my English teacher. All in all, not such a good result.
And they never did give me a mark for that paper.
Anyway, all that's just a round about way of introducing a list of some of my favorite long poems (they've all been road-tested):
John Keats: Isabella (or The Pot of Basil)
Thomas Grey: Elegy Written in a Country Churchyard
Robert W. Service: The Ballad of Blasphemous Bill
Matthew Arnold: The Scholar Gypsy, The Forsaken Merman and The Voyage of St Brandon
I couldn't find that last one online, which is a shame because it's got some great passages in it. Maybe, one rainy day, I'll type it out and post it here. Until then, you're on your own.