Controversial new tests for four-year-olds will be introduced in 2016, the government announced today, as it laid out its final plans for a new-look system of assessment.

But in an unexpected twist, the new baseline tests will not be compulsory, giving schools the option to be judged on attainment alone at Year 6. 

Proposals to rank pupils by decile - telling parents their child was in the top or bottom 10 per cent - have been dropped after widespread opposition.

Ministers revealed that the baseline assessment will be taken at “the earliest possible point in school”, thought to be the first term of reception when most children are four. Schools will be able to choose from a number of approved assessments.

The tests will then be used to assess how much progress students have made between age four and 11.

However, schools can choose not to use any of the approved assessments and will instead be judged on the test scores of 11-year-olds alone from 2023 onwards.

Under the reforms, 85 per cent of pupils will have to pass the expected standard in reading, writing and maths in Year 6. The existing floor target is 65 per cent.  

But according to Russell Hobby, general secretary of heads’ union the NAHT, many schools will opt for the new baseline tests as leaving it to the final year would be a gamble many schools would be unwilling to take.

Having good progress will keep a school above the floor targets, whatever the attainment of pupils, he said.

“An attainment target of 85 per cent will put about 12,000 schools below the floor,” Mr Hobby said. “But it is not just 85 per cent attainment, if you have good progress then you can fall below 85 per cent attainment and there are no penalties associated with it.”

If schools fall below the floor target, the government will investigate and intervene. If a school is deemed to be failing, the headteacher can be removed and the school turned into an academy.

Plans for the new baseline measures were viewed as being highly controversial when they were proposed in a consultation paper last year, particularly among the early years sector. Many fear the changes could lead to more pressure to ‘schoolify’ the play-based reception year.

In the consultation response published today, just 34 per cent of respondents supported the introduction of a baseline test at the start of reception - 51 per cent were against the move.

The current early years assessment, called the early years foundation stage profile, comes at the end of the reception year and is a broad assessment of pupils’ abilities and will become optional from 2016.

The teacher assessments for children at age 7 will remain. At age 11, externally-set tests in reading, grammar, spelling and punctuation and mathematics will be taken by all pupils. A sample of pupils will also take a science test.

But the idea of ranking pupils has been dropped after the plans came under significant criticism. The original proposal included an example of a school report that stated: “Tom received a scaled score of 87. This places him in the bottom ten per cent of pupils nationally.”

Under the reforms, parents will still be given the results of their child’s tests as scaled score - a score based around 100 where 100 denotes the standard expected for that age. Decile rankings, in which children are placed into ten per cent groupings, have been dropped.

Schools minister David Laws said: “In primary schools, we are raising the bar to improve standards and introducing a proper measure of progress from when children start school to age 11.

“I want to see all children leaving primary school with a good standard of reading, writing and maths so that they can thrive at secondary school. A better start at secondary school is a better start in life.”

The reforms come after changes to the secondary accountability system, which announced that schools would receive a year’s holiday from Ofsted inspections if their GCSE results improved significantly.