The testing system for seven and 11 year olds in England is to be overhauled. What are these tests? And what are the arguments for and against using them?
What tests are taken?
Tests are meant to reflect the emphasis in primary schools on the basic skills of literacy and numeracy.
Pupils at the age of seven, have to take tests in English and maths. For English, these assess areas such as reading, writing, handwriting and spelling. And for maths, there are questions about number skills, patterns and problem solving.
For 11 year olds, the tests cover English, maths and science. And for English at this age, pupils are assessed on areas such as sentence structure, punctuation and composition skills.
Pupils are assessed in terms of the "level" they have reached - and in education-speak, government ministers talk about the number of pupils "reaching the expected level".
What are the complaints against these tests?
Parents have complained that the age of seven is too young for formal tests, and that children can become over-stressed by the experience. Instead of enjoying school, there are claims that these pupils start worrying about becoming failures.
Teachers have been longstanding opponents of tests - and the biggest teachers' union is currently threatening a boycott. They say that the tests get in the way of teaching - with schools becoming obsessed with how well they score.
In particular, they dislike the way that test results for 11 year olds are used in school league tables, which they say can pressure schools into cramming for the tests rather than providing a broader education.
What's going to change in the new-look tests?
The government says that the principle of using tests is still a good one - but it will change the focus of how tests are applied.
For seven year olds, the formal, externally-marked tests will be given less prominence - and assessments by teachers will be given greater weight.
There will also be more flexibility about when the tests are taken, as part of a package intended to soften the impact of the tests, and to create a more light-touch regime.
For 11 year olds, the tests will continue, but the national target, which ordered that 85% of pupils would reach expected levels of achievement by next year, have been postponed.
Instead schools will be allowed to set their own "challenging" targets - which is intended to tackle accusations that centralised targets ignore local conditions. For instance, some schools passed the 85% hurdle years ago, while for others, in tougher circumstances, they felt they were being set up to fail.
Why has the government defended the tests?
They argue that tests and targets have been central to the improvements in primary school standards - underpinning the literacy and numeracy strategies.
And they point to the evidence of international league tables of school performance, which show English primary schools as having among the highest levels of literacy skills in the developed world - only beaten by Sweden and the Netherlands.
They also say that without this pressure of tests and targets, many schools in deprived areas would have continued to perform badly, with little expectation that their pupils would ever escape a cycle of underachievement.
Ministers have highlighted the strong link between success at primary tests and the qualifications which would affect their later life chances.
If children reach the expected levels at the age of 11, there is a 70% chance that they will get five good GCSEs. And among pupils who failed tests at 14, there is only a 5% likelihood that they will achieve five good GCSEs.