Grandmaster Thornton started Taekwondo on Vancouver Island at the age of 7 under the instruction of Grandmaster Woo Kim. By the age of 16 he started teaching at the rec centre, where he first started. By the age of 19 the Woo Kim Courtenay School was one of the largest schools in the association. At the age of 22 he moved to Korea to further his education in the sport, where he trained with some of the top teams in the world. In 2004, at the age of 30 Grandmaster Thornton moved home and opened the Woo Kim Surrey Taekwondo School. Now he has become one of the leading masters in the sport of Taekwondo in the Province and the Nation.