But Estonia has also taken a deliberately inclusive approach, argues Mart Laidmets, a senior official at its ministry of education. It tries to avoid at all costs having pupils repeat years of school. Holding pupils back can help. But too often it is used as an excuse not to teach difficult kids. It may also reflect bias or discrimination. In countries such as Russia, Slovakia and the Czech Republic, poor boys are especially prone to being kept back a year, despite decent academic achievements.
Estonia, like Finland and Canada, also tries to keep selection by ability to a minimum. It delays “tracking” children into academic or vocational routes until they are 15 or 16 years old. Mr Laidmets argues that it helps pupils find jobs later in life, since better maths and literacy make it easier for them to adapt to changes in the labour market and to earn new skills.
By contrast, where pupils are diverted from an academic track at an early age, whether towards a vocational school or a less rigorous class in the same school, the gap between rich and poor children tends to be wider. In the Netherlands pupils at vocational schools have results equivalent to about three years less of schooling than their peers at general schools. “The more academically selective you are the more socially selective you become”, says Andreas Schleicher, the head of education at the OECD.
All of which suggests what countries should not do. But are there any sure-fire tips from the best performers? Or is their success just down to pushy parents and tuition after school?
Culture matters but so, too, does policy, says Lucy Crehan, author of “Cleverlands”, a new book on PISA-besting countries. She points out that most of these states delay formal schooling until children are six or seven. Instead they use early-years education to prepare children for school through play-based learning and by focusing on social skills. Then they keep pupils in academic courses until the age of 16. Even Singapore, which does divert some pupils to a vocational track at the age of 13, ensures that pupils in those schools keep up high standards in reading and maths.
Top performers also focus their time and effort on what goes on in the classroom, rather than the structure of the school system. For while test scores and pupils’ economic background are linked across the OECD, so too are specific things that the best schools and teachers do (see chart 3).