The competition, You Can't Jail Minds, is inspired by the experiences of Irina Ratushinskaya in the former Soviet Union, Jack Mapanje in Malawi, and a number of detainees at American-run prison camp Guantanamo Bay.
All produced moving poetry, despite being banned from using pen and paper. Instead, they used everyday objects such as toilet paper or disposable cups from their dinner trays to etch their words.
To reflect this, pupils are being asked to compose their poems on unusual objects such as paper plates, toilet paper and clothes.
Moazzam Begg, a British national who spent two years in Guantanamo Bay, hopes the competition will open pupils' eyes to "some of the atrocities that are happening across the world today".
He said: "My experience of Guantanamo Bay will haunt me for the rest of my life. I turned to poetry to keep my hopes alive and to ensure that my experiences there would not be forgotten.
"I had access to pen and paper, but so many others at the camp didn't - they had to resort to using toothpaste and pebbles to record their emotions."
The closing date is March 20.