Vocational options for teenagers should be much better so the talents of non-academic pupils are not wasted, says Ofsted chief Sir Michael Wilshaw.
The education watchdog warns of a "one-size fits all" model in England which leaves behind young people who do not succeed in exams.
Better vocational training would reduce youth unemployment, says Sir Michael.
"We simply have to improve the quality of our technical provision," insists the Ofsted chief.
The Department for Education says pupils are now "better prepared for further study and more ready for the world of work".
Sir Michael says that complaints about the quality of vocational education have been made for 50 years, but without sufficient improvement.
"I can almost sense eyes glazing over when I say this," he says.
But he argues that it is a "moral imperative as well as an economic one that we do something now to change direction".
Sir Michael says there must not be another "false dawn" in improving vocational options and "the country cannot continue to fail half its future".
He warns that vocational training should not be a "dumping ground for the disaffected and cater just for the lower-ability youngsters".
The Ofsted chief says that some European countries, such as Germany and Switzerland, had lower youth unemployment rates because of a better training system.
This reflects a recent survey from City and Guilds that showed how the most developed vocational systems were linked to better rates of youth employment.
At present, Sir Michael says the education system in England does not offer enough opportunities for those who do not succeed at GCSEs.
A Department for Education spokesman said: "We know that young people benefit from studying a strong academic core of subjects up until the age of 16 which they can complement with additional arts subjects or vocational qualifications.
"That's why we are making the EBacc the expectation for every child who is able.
"Our reforms are leaving pupils better prepared for further study and more ready for the world of work, with the result that we now have the lowest number of Neets on record and the highest ever number of young people going into higher education."