Get your 14 to 16-year-old students to use their calculators to solve problems over the four weeks of May 22-June 19 and they could win a watch, boks and calculators for themselves andor their school. With the "Keyed-in with Casio" competition, problems will be set each week on the Stanley Thornes website at www.thorneseducation.com and students will answer on-site. A full set of correct answers will reveal three jigsaw pieces containing words and symbols and at the end of the month the 12 pieces fitted together will reveal the final problem to solve and a tie breaker. Every week 10 students will win a copy of "On Course for GCSE Maths" and a Casio fx-83 WA calculator. The overall winner will receive a watch and a class set (20) of Casio fx-7400G Plus calculators.