However, it does raise questions about some existing taken-for-granted's in educational research, which in itself is helpful and a reason to do more studies using non-linear models like this one.

Instructional practices was operationalised through the German three-factor model, with cognitive activation the main measure. My view is that this model doesn't work (the findings are very inconsistent across studies), and this may be another factor.

Does this mean we need to jettison the existing model? Not quite yet. There are a number of limitations in the PISA-TALIS linked dataset. Leadership was conceptualised as distributed and instructional, but each only had a few variables in the dataset.

We did not find the traditional causal model of leadership leading to better attainment through instruction. Rather, the relationship was highly complex, and in fact we found clusters of high attainment where scores on the measured leadership and instructional practices were low

The results (again!) suggest that explicit teaching is the most appropriate way to help low achievers from disadvantaged social backgrounds acquire new, complex, and structured mathematical knowledge

Yes, I agree

1. Ensure that subject knowledge is an important part of teacher education programmes
2. Provide CPD opportunities for teachers to develop subject knowledge when & where they need it
3. Provide high quality support materials and textbooks to scaffold teacher knowledge

Of course, not all teachers can have a subject degree in the subject they teach (in secondary). And in primary all teachers are generalists by definition. So what can we do to ensure that the subject knowledge is there?

Interestingly, the effect is mediated by teacher confidence, with teachers with a subject degree being more confident. That is similar to what David Reynolds and me found in an earlier study, and a body of evidence on the importance of teacher subject knowledge.

Subject degree is positively related to attainment in TIMSS (across countries), and explains about 17.5% of differences between teachers in effectiveness, which is a practically important effect. The effect is strongest for pupils from more disadvantaged backgrounds.

‪And in more great news Christine Counsell will be chairing the curriculum reform task force.‬

www.education-ni.gov.uk/publications...