The government has had to re-issue its Sats guidance how to prepare for the Sats after it got a sum wrong in its original publication. 

The guidance, from the Standards and Testing Agency, gives teachers a list of equipment needed by 7 and 11-year-olds taking maths tests next year.

But it was an example of how to answer a “reversed number sentence” which caught the eye of educators.

The example given was an empty box followed by = 936 + 285. Pupils had to fill in the empty box. The guidance said that 1,121 would be given one mark.

But sharp-eyed educationalists pointed out that the correct answer was 1,221.

This morning, the government re-issued the guidance which now has the correct answer given.

The guidance also advised teachers that answers to questions involving common fractions in key stage 2 should be given in the simplest form.

Pupils who give several answers including the correct and incorrect answers will not get a mark, it said.

It added that there would sometimes be questions on the three times multiplication table at key stage 1 - although this is not in the national curriculum. This, it said, reflects the requirement that children are expected to count in multiples of three from 0.

The guidance comes less than two weeks after a review into the circumstances surrounding two leaks of Sats papers in 2015.

The review found that there were “substantial issues” at the Standards and Testing Agency, including a “lack of end-to-end strategy, data and oversight; a defensive and silo culture; a shortage of commercial skills; and an ineffective assurance process and culture”.

A Department for Education spokesperson said of the maths mistake:

“This was clearly an unfortunate proofing error. It was identified and corrected within 24 hours of publication. We are reviewing our checking procedures to address this.”

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