Children starting secondary school this week will be the first required to stay in education or training until they are aged 17.

The changes are being made in an attempt to reduce the number of young people who leave school without qualifications.

The mandatory school leaving age will rise again to 18 for next year's secondary school starters.

Ministers have warned that the number of non-skilled jobs in Britain will fall over the coming years, leaving many teenagers unable to get a job if they do not have academic or vocational expertise.

Only around three-quarters of 16-18 year olds are presently in full time education or vocational training.

When this year's secondary starters reach 16 they will have a choice of pursuing education or training at a school, college, or a work-based training scheme or as part of a job.

Those going into employment will have to spend at least one day a week in training.

A number of revisions to the curriculum are also being brought in this week, prompting head teachers to complain they are overworked.

Sixth-form pupils starting their two-year A-level courses will be able to aim for a new top A* grade to reward the highest marks.

New diploma qualifications for 14-19 year-olds in subjects like construction and engineering are being introduced for the first time.

In addition, the secondary school curriculum for 11-14 year-olds is being altered to give schools greater flexibility over teaching.

The Association of School and College Leaders (ASCL) said last month it was concerned about the "work-life balance" of senior staff and head teachers as they oversee a raft of changes.

ASCL General Secretary John Dunford said: "Problems recruiting and retaining heads and other senior leaders will continue as long as their workload remains disproportionately heavy."

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