A kind of analysis. Comparison and Contrast papers place the similarities and differences of two or more poems side by side for discussion. It's easiest to choose two poems with much in common. Find unsuspected resemblances, not just obvious ones. Do the same for differences.
Organization is tricky.
DO NOT isolate the two poems in your discussion. You might consider comparing and contrasting the poems side by side all the way through. This organizational strategy allows you to organize your paper into discussions of theme, metaphor, etc. Textual support is essential to a good essay, no matter which approach. The same caution and care should be taken when quoting poetry as when quoting books, journals, periodicals, etc.