Children who have enjoyed a "golden, gilded" school life should be made to fail to teach them important lessons like how to bounce back from defeat, the former head of Eton has suggested.
Tony Little said that, as a headmaster, he always worried the most about the school leavers who had always been popular, smart and had little difficulties to deal with.
It should be a school's duty to ensure that all of the pupils experience failure at some point, and are able to learn from it, he suggested.
Speaking at the Global Education and Skills Forum in Dubai, Mr Little, who is now chief education officer of GEMS Education, said that as a headteacher, he would see each of his 18-year-old pupils individually.
"You would remember as you saw each young person their journey, their experience. And some of these had been pretty straightforward, a lot of them had been bumpy along the way.
"But the only ones who worried me, as I shook hands and said my farewells, were the boys and girls who had gilded school experiences. The golden schoolchildren, for whom it had been very straightforward. Always good at exams, always popular, always found the flow easy to deal with, they never really had anything significant to bump up against."
He added: "I think it behoves all great schools to make sure all their children fail. Not just have the experience of failure, but of course within a supportive context, to learn from that experience of failure."
Mr Little that said the high-stakes nature of exams and testing means that it is difficult to do this in terms of academic work, but that there are other ways that schools can teach this lesson.
"It's not the fact of being dropped from the sports team, it's how that is dealt with, how young people are enabled to bounce back and find their way to regain that level or even higher," he said.
The former school leader warned schools against focusing too heavily on one sport or activity, arguing that activities of all types should be celebrated equally.
"I visit an awful lot of schools which are lop-sided," Mr Little said. "And at worst this can be quite pernicious.
"I worked in one school where rugby was king, everything revolved around it, the fly-half was a god. I used to long for the school team to lose. It just mattered too much and it was taking away from young people's other experiences because it was being focused in this very specific and rather limited way.
"Coupled with that is the idea of parity, we celebrate success in an even way. There aren't many schools I've visited where, for example, the child or the young person, who leads a social enterprise is given equal kudos to the one who is captain of the top sports team or a star actor.
"It behoves schools to think through their policy of celebration. What it is young people respect each other for."
Mr Little also said that it is important that schools have respect for young people.
"I still visit far too many schools which seem to be run, principally, for the benefit of adults, rather than hold children at the centre of the experience," he said.
"This can be articulated in a whole variety of ways. But by respect I mean creating a culture of support. Broadly speaking it's a yes culture. If any child has a good idea and wants to develop something in a different way, the school should do its damndest to try and make it happen. If that means raising money from outside the school to enable a certain type of activity that the school can't run to take place, then so be it. That's where the energy should go."
Mr Little was headmaster of Eton College - which counts Prime Minister David Cameron, the Duke of Cambridge and Prince Harry among its former pupils - until last summer.