Here is a maths problem:
1. Poor children at schools in areas where there is selection do worse than poor children at schools where there is not selection.
2. Poor children at selective schools do very slightly better (one eighth of a GCSE grade) than poor children at non-selective schools.
3. Through mechanisms not yet made clear, the government say that they will increase numbers of poor children at selective schools. This may help that tiny number by one eighth of a GCSE grade.
4. According to the law of ratios, however, increasing selection will penalise more poor children in the non-selective (ie Sec Mod) schools than now.
5. QED increase number of grammars, increase number of poor children being penalised by selection.
6. My maths was never good. Am I wrong?