Robert Frost's "What Fifty Said"

When I was young my teachers were the old.
I gave up fire for form till I was cold.
I suffered like a metal being cast.
I went to school to age to learn the past.

Now when I am old my teachers are the young.
What can't be molded must be cracked and sprung.
I strain at lessons fit to start a suture.
I go to school to youth to learn the future.

"What Fifty Said" - Robert Frost (1928)