Eleven youngsters with serious behavioural problems from special schools across England embark on a life-changing challenge - trekking the Himalayas towards the world's highest mountain, Everest. But they cope with the worst seasonal weather for almost 20 years and for some pupils, the added difficulty of altitude sickness. In the first of this two-part programme, a BBC team follows the challenges they face, and the lessons they learn in the highest classroom on earth. Show less