Image copyright PA Image caption Nicky Morgan said it was "tacit snobbery" to restrict pupils from taking core academic subjects

Primary school pupils in England could face formal tests at the age of seven - and a pool of "elite teachers" will be recruited for struggling schools.

Education Secretary Nicky Morgan has announced a package of measures aimed at tackling underachievement.

There will be a target requiring 90% of pupils to take core academic subjects at GCSE.

Head teachers' leaders warned a teacher shortage in some subjects made that target "immensely challenging".

Mrs Morgan said more "robust and rigorous" checks on progress at the age of seven would help ensure that all pupils had "mastered the basics" before they left primary school.

Recruiting teachers

At present, she said, there are 20 local authorities where most pupils do not achieve five good GCSEs, including English and maths.

The education secretary wants to target areas with low achievement, such as coastal towns and some northern cities.

Image copyright PA Image caption Schools will be expected to make sure 90% of pupils take core academic GCSEs

But Labour's shadow education secretary Lucy Powell said that rather than raising standards, the government has caused a "chronic shortage" of teachers.

In a speech on Tuesday, Mrs Morgan announced details of the pre-election pledge to create a National Teaching Service.

This will recruit a pool of 1,500 high-achieving teachers over five years who would be deployed to schools in areas with weak results, such as coastal towns.

There will be financial incentives for teachers to join this project, with staff expected to stay for up to three years.

"Too many young people aren't being given a fair shot to succeed because of where they live," said Mrs Morgan.

"Coastal towns and rural areas struggle because they struggle to recruit and retain good teachers, they lack that vital ingredient that makes for a successful education," said the education secretary.

"The National Teaching Service will play a key part in solving this problem."

Brian Lightman, leader of the ASCL head teachers' union, welcomed the National Teaching Service as a way of helping schools in parts of the country where they "simply cannot recruit teachers".

Tougher tests

The education secretary has also signalled changes to the assessment system for primary and secondary pupils.

As well as the "baseline tests" when pupils start in Reception and national curriculum tests, often known as Sats, taken at the age of 11, the government is looking at a tougher approach to tests at the age of seven.

Image copyright ASCL Image caption Brian Lightman says schools are struggling to recruit enough specialist teachers needed for core academic subjects

At present, there are teacher assessments, with schools sending their results to local authorities, but a consultation will consider moving to gathering results at a national level, perhaps with external testing and the publication of results.

"To be really confident that students are progressing well through primary school, we will be looking at the assessment of pupils at age seven to make sure it is as robust and rigorous as it needs to be," said Mrs Morgan.

There will be a consultation on changes, with the aim of creating a clearer measure for how pupils are progressing through primary school.

In secondary school, there is clarification of the target that all pupils will have to take traditional GCSE subjects, in the English baccalaureate.

This requires pupils to take GCSEs in English, maths, history or geography, two sciences and a language.

There will now be a target of 90% of pupils, which will allow exemptions to be made by head teachers, such as for pupils with special needs. At present, about 39% of pupils take these subjects.

Mrs Morgan said it was "right that every child studies a strong academic core up until the age of 16".

And she said it was "tacit snobbery" to think that some pupils, usually from poorer families, were not suitable for learning these key academic subjects.

It was unacceptable for adults to "write off" children's chances to take these academic subjects "before they've even turned 15", she said.

'Exam factories'

Mr Lightman said it would be "immensely challenging" for schools to get enough staff for subjects such as modern languages to make the target achievable.

Image caption More "robust" tests would prevent pupils from falling behind before leaving primary school

Russell Hobby, leader of the National Association of Head Teachers. warned of "turmoil" for schools, if the push for so many pupils taking EBacc subjects took when schools were already trying to implement the new "Progress 8" way of measuring school performance.

Labour's Lucy Powell said that rather than "drive up standards", the government had a "schools policy that has allowed the attainment gap between poorer children and their peers to widen" and created "teacher shortages particularly in subjects that are key to our country's competitiveness such as English and maths".

Kevin Courtney, deputy general secretary of the National Union of Teachers, said: "It is quite staggering the degree to which the government is unable to understand how their approach to the measurement of the performance of schools, and the system as a whole, is turning schools into exam factories."

The current system already meant that England had "the most excessively tested children in the whole of Europe", said Mr Courtney.