Chimamanda Ngozi Adichie, an admired African novelist, once said ‘show a people as one thing, as only one thing, over and over again, and that is what they become’.

It sounds like a cliché but it applies neatly to the portrayal of our schools and students.

This week the Herald released its annual league tables ranking all secondary schools on the basis of 2015 academic results.

If you were a parent wanting to choose a school for your child and you valued academic excellence, you would naturally start at the top of those league tables. And likely to no surprise, you will note that the most successful schools are in the leafy suburbs.

Typically, higher decile schools are rewarded with public praise while lower decile schools are punished. Schools that have not met national targets are labelled as poor performers.

However the story is incomplete because the rankings fail to show how much each school helped its students to improve. Should a school that brings its students from years behind national benchmarks to only a few months behind be considered a failure?

This is an area the Initiative has been looking at in our project on school failure. The first report in the series makes a case that New Zealand needs better metrics of school quality.

The issues identified in the report are not unique to New Zealand. Indeed for the second phase of the project, I will visit Washington DC to learn about how improved measures of performance have supported student achievement.

The DC Public School district has in recent years revamped their teacher evaluation processes to include measures that show how much students learn in different classrooms. Initial reviews show overall improvement in teacher quality and in student learning outcomes.

In New Zealand, current indicators of performance do not take into account students’ backgrounds. Principals and teachers may then be fighting a battle they cannot win if their quality continues to be judged on matters they cannot control.

The young students too are impressionable. If their schools continue to be consistently ranked at the bottom of the performance tables, they may start believing that the bottom is all they can do.

The DC example provides an opportunity to learn from other jurisdictions that are being innovative in their school improvement approaches.