That may explain the paradox that, after primary school, there seems little or no relationship between class size and educational achievement.McKinsey argues that the best performing education systems nevertheless manage to attract the best.
None of the countries with a high degree of stratification, whether in the form of tracking, streaming, or grade repetition is among the top performing education systems or among the systems with the highest share of top performers.
Ironically the OECD education directorate itself says academically streaming children is a bad idea, and the best performing education systems eschew it.
He said Finland had the world's "best performing education system," partly because of its highly effective way of recruiting, training and supporting teachers.
Evidence also shows how high performing education systems engage teachers to set their own teaching and learning targets, to craft productive learning environments, and to design multiple forms student assessments to best support student learning and school improvement.
It says that school choice and competition are not related to improved performance; autonomy over the curriculum and assessment appears to improve performance; the percentage of students enrolled in private schools is not related to a system's overall success; and the highest performing education systems are those that combine excellence with equity.
I cannot emphasise enough how important it is for me, personally, that we learn from the highest performing education systems – some of whom I am delighted to see represented here – and I am very grateful to everyone who has taken the time and trouble to come to London for this event.
It shows that Northern Ireland is Europe's top performing education system for primary maths.
