An essay contest sponsored by the Boys and Girls Clubs of Dorchester has a big pay-off for young football fans: Their winning entry could get them a chance to play on the field at Gillette Stadium with Tedy Bruschi on June 20. The contest is open today through May 11. Entries should be 3-5 paragraphs in length on the importance of teamwork. Essays should be submitted to Emily Capurso at firstname.lastname@example.org . Call Mary Kinsella Scannell with questions: 617-288-7120.