Conceived 100 years ago for a different population, today's high schools are obsolete, says Leon Botstein, president of Bard College in the US. He proposes sending 16-year-olds off to work, college or a new form of vocational education.

"By the age of 16, school is wildly out of step with the actual realities of America," says Botstein, who argues high school was created for teens who were far less biologically mature and far more insulated from adult culture.