A "one size fits all" education system is failing some of England's schoolchildren, according to Sir Michael Wilshaw.
Less academic youngsters deserve a good education, the Ofsted chief will say in a speech, warning that not enough is being done for those who want to pursue a more technical path.
He suggests that other nations, such as Germany and Switzerland, have more flexible education systems that meet the needs of both students and their economies, and as a result they have lower youth unemployment levels than the UK.
In his address to the CentreForum think-tank, Sir Michael will acknowledge there is a need for a strong, core academic curriculum, but that children who are not academic should not be neglected, the Guardian reported.
"They too deserve an education worthy of the name," he will say.
"The country cannot continue to fail half its future. The great comprehensive school head teacher knows that a 'one size fits all' model of secondary education will never deliver the range of success that their youngsters need. Some of our international competitors understand this probably better than we do.
"Their education systems are more flexible than ours and are much more geared to aligning the potential of the student with the needs of their economies. As a result, countries with excellent academic and technical routes have far lower youth unemployment than we do."
Sir Michael is also expected to say that the education on offer for children who do not do well at age 16, or who do not want to follow an academic route, is "inadequate at best and non-existed at worst".
Teenagers who fail to gain at least a C grade in their English and maths GCSEs "make little or no progress" in college two years later, he will suggest, arguing: "Our responsibilities as educators do not end when students fail to attain our targets.
"On the contrary, the written off and the 'failed' need our help most and we should never forget it."
The Ofsted chief is expected to warn that too many students are being left behind at age 16 and left disadvantaged because of "uniformly weak" careers guidance and poor preparation for the world of work.
Sir Michael's speech comes amid a continued push by the Government to encourage children to study traditional subjects, including English, maths, science, a foreign language and either history or geography, up to GCSE. Ministers have argued that studying these subjects will give children a good grounding for their future.