We’ve seen an extraordinary change in school accountability this year. Normally when I say things like that I’m talking about radical change in performance measures imposed on schools by the DfE. This time I’m delighted that the change has been led by schools. This was the year that collaboration became a ‘thing’.

With such high numbers of schools electing to share their results via SISRA, so that around 185,000 pupils are included, we can be pretty confident that early estimates for Attainment 8 averages are going to be close to the final results. This all means schools will know their Progress 8 scores accurately enough for the start of term.

Being able to look at the emerging national picture based on your shared results is incredibly helpful. It looks like the Ebacc component of A8 averages have gone up, which is all down to the reforms in GCSEs and more points being available for those subjects in 2018. But the open element averages have gone down considerably. I believe this is mainly due to the removal of the ECDL qualification. These two changes have acted to cancel each other out in overall terms, but individual schools might find changes in their P8 based on their curriculum mix.

But the really exciting part of this collaboration is nothing to do with headline measures. Real accountability is about pupils. How well did they do in each subject, and how do we know? To answer these key questions we need subject level tools which compare results with entries in the same subject. We need to compare like with like.

Hence I am delighted that SISRA have developed two new tools to do just that using transition matrices and subject value-added (which will be known as Subject Progress Index or SPI for short). These tools show us how grades are distributed by prior attainment so we can be clear what good progress looks like.

These graphs show the value added in the reformed science GCSEs based on the collaboration, and can be used to see which grades are above or below average by prior attainment.

You will see that, on average, pupils with higher ability get noticeably higher grades in the separate sciences than their peers who entered combined science. Historically many schools enter their more able pupils for biology, physics and chemistry rather than core and additional or, this year, the new double science in the belief that they are more challenging, but this graph casts doubt on that. It’s worth reflecting therefore whether more pupils might benefit from taking separate sciences.

This is the sort of information which school leaders need to make important decisions about performance and curriculum planning early in the school year. By sharing your data, you help leaders everywhere. Thank you for doing it. Thank you for helping us all to move towards a school-led, self-improving system.

Duncan Baldwin, Deputy Director of Policy, ASCL