A man and a 14-year-old boy from Britain have died in a motorway crash involving a lorry and two coaches near Cologne in Germany.
Stuart Dines from Thomas Mills High School in Framlingham, Suffolk, was travelling on one of the coaches.
The assistant driver on the other bus, carrying pupils from Norwich School in Norfolk, also died. The two schools were on separate ski trips to Austria.
More than 100 people were involved in the accident and more than 20 injured.
Two people are being kept in hospital. One is described as being in a life-threatening condition.
Children had to be treated on a grass verge, and a nearby fire station and school were used as makeshift first aid centres.
The shocked pupils are now heading back to the UK on board two coaches after their holiday was cut short.
Colin Hirst, 51, headteacher at Thomas Mills High School, said Stuart had been "a very active and popular member of the school... not just with pupils but with staff".
"He always had a smile on his face," he said.
The teenager was on a coach that had stopped on the A4 motorway's hard shoulder after suffering a puncture at about 0220GMT, between Kerpen Buir and Duren, south west of Cologne.
A lorry ploughed into the stationary coach and a second coach, carrying the pupils from the private Norwich School, then collided with the two vehicles.
A British man, believed to be an assistant driver who had been seated at the front, was killed.
Mr Hirst added: "My understanding is that the coach had broken down and had pulled over on to the hard shoulder with its hazard lights flashing.
"A lorry then hit the stationary coach, jack-knifed and was then in collision with another coach which was travelling along the autobahn."
British Consul-General Peter Tibber said Stuart was killed by a piece of metal from the lorry which smashed through one of the coach windows.
The second, smaller, coach, owned by Ambassador Travel, of Great Yarmouth, had been carrying the teenagers from Norwich School, who were on their way to Schladming, in Austria.
Deputy head Adam Pettitt said: "All our pupils are out of hospital now. Our thoughts go out to the other school involved."
Counsellors will be on hand when Thomas Mills High School pupils arrive back in the UK.
Their coach had been carrying 55 pupils, aged between 12 and 16, accompanied by six members of staff. It was operated by GT International, based in Worcester Park, Surrey.
The party was on its way to Fujen in the Ziller Valley in Austria for a one-week trip.
The Foreign Office has set up an emergency helpline on 0207 008 0000.