Welcome back to the surreal world of primary accountability mixed with the chaos of primary assessment.

It’s a heady cocktail. 

The floor standard defines unacceptably low performance. It has two halves: attainment and progress. 

As a result of last year’s assessment reforms, around half the schools in the country will be below the attainment floor. The highest scoring local authority got just 2 per cent more than the floor on average. 

Despite other measures saying our schools are the best they have ever been, our government is looking primary teachers in the eye and claiming that their achievements are unacceptably poor. And claiming credit for an improving school system. 

The other half of the floor standard, the progress floor, is published today. It is set at -5 in reading and maths, and -7 in writing. If you got more than that on progress you are above the floor full stop. In fact, so unpredictable were the effects of assessment reforms that the government had to promise that no more than six per cent of schools could be below the progress component of the floor standard. 

How real can these measures be? 

As predicted, there is huge variation in marks in reading and writing between local authorities. In the reading test, two thirds of children who sat it got less than 42 per cent of the answers right.

Where is the room to demonstrate progress for low to medium attainers?

We can have little confidence in the writing results - as national statistics they are suspect. The standards of evidence in different moderation visits were widely different due to the late and ambiguous guidance provided.

In one you need to show evidence of each standard across six pieces of work. In the next you needed evidence of each standard in each of six pieces of work. In the next you needed evidence of each standard three times in each of the six pieces of work. 

These were poorly designed and implemented tests. That can happen with new tests, we can learn and improve by working together.

But, children’s prospects and teachers’ careers hang on this experiment. That’s not fair. 

The data generated by these tests should not be used for interventions. It should not be compiled into league tables. It should not be used to provide a floor. It should not be used to sack people.

It is time for the government to stop imposing flawed designs and work with the profession to design a fair, coherent and meaningful system of assessment and accountability.

We are very reasonable in what we ask for. We accept both accountability and testing. We just want the judgements to be fair. 

Russell Hobby is general secretary of the NAHT headteachers’ union. He tweets as @RussellHobby

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