Primary schools have disclosed controversial data about pupil achievement, with the surprise revelation that children in bigger classes and bigger schools get better grades.
The Herald on Sunday has conducted a comprehensive survey of schools’ national standards results, before the Ministry of Education publishes them this week.
At schools with fewer pupils for each teacher, around 70 per cent of children are achieving national standards in reading, writing and arithmetic. But at schools with more pupils for each teacher – in effect, bigger classes – the pass rates rise to about 80 per cent.
So too with school rolls: the highest proportions of children achieving or exceeding national standards are at big schools.
I’ve just checked the data – and they’re absolutely correct! There’s a strong linear relationship between class size and National Standards results. Here’s a scatter plot for reading results vs class size.
Bigger classes are better! Just like Treasury and the government said! But wait, what’s that cluster of very small classes with very poor results down there in the lower left quadrant? Well, those, which have well below standard in every single category are:
Blomfield Special School & Resource Ctre
Waitaha Learning Centre
Kea Street Specialist School
Hamilton North School
Sir Keith Park School
Every single one of which is a school for children with disabilities. Take them out of the dataset and see what happens to the trendline:
Most of the other low-quality, low ratio schools I note that they’re predominantly low-decile schools in rural areas. So now we know that very poor, very small schools aren’t that great for the kids.
Update: updated the charts after the statisticians chastened me for improper plotting, and added the regression co-efficient by (actually rather popular) request.