claig, you say that you want grammar schools and selection in order to promote social mobility and better academic chances for working class kids.
The data shows that selective school systems actually causes greater social inequity, the earlier the selection, the worse the outcomes.
"Across the OECD countries, mean student performance in reading literacy tends to be lower in countries with a high degree of institutional differentiation and selection at an early age, as compared to countries with integrated secondary school systems where selection has not taken place at the age of 15. Even more importantly, the share of the OECD average variation in student performance that lies between students and schools tends to be much higher in countries with early selection policies. While this, in itself, is not surprising because variation in school performance is an inevitable outcome of stratification, the findings also show that education systems with lower ages of selection tend to show much larger social disparities.
The reason why the age at which differentiation begins is closely associated with social selectivity may be explained by the fact that students are more dependent upon their parents and their parental resources when they are younger. In systems with a high degree of educational differentiation, parents from higher socio-economic backgrounds are in a better position to promote their children?s chances, whereas in a system in which such decisions are taken at a later age students themselves can play a bigger role.
In sum, PISA 2000 results show that students in integrated education systems perform, on average, better than those in selective education systems, and that their educational performance is less dependent on their background. Many factors may be at play here. A higher average performance suggests that the more heterogeneous student groups or classes in integrated education systems could have a beneficial effect for the lower-performing students. Also, the flexibility offered by an integrated system may allow students to improve their performance while keeping their academic options open."
This is the result of a study of many different school systems in various countries.
www.oecd.org/dataoecd/15/20/34668095.pdf (see page 89)