I used A Psalm of Life by Henry Wadsworth Longfellow for memory work with my students. I began with the Mensa for Kids #10 Poem template, and then broke the poem down into three practice lessons, which left students to fill in the missing words. After several rounds of practice and dedication, the students were able to recite the complete poem :) We also memorized famous speeches, including Elizabeth I, Lincoln, Henry, Roosevelt, and more.
You can download the poem practice templates as well as speeches to memorize in this supplementary post to A Guide to Surviving the Great Forgetting.