Why average GCSE pass rates of non selective schools so low?

[Choco]

Rather than comparing the whole school results, if you look at the government performance table website you can see GCSE results by prior attainment. If you consider your DC to be a higher attainer, then look at the achievements of an individual school for higher attainers. These tables look at the starting point on entry to secondary school at 11 and show outcomes for high, middle and low attainers. You will see hig attainers do much better than the average in all schools. In some it will be similar to Grammars.

This should help you choose a back-up option and feel more confident about it.