Many readers will remember being in streamed classes at school. Perhaps you were in a top English class but a lower maths class. 

Streaming is commonplace in New Zealand schools and has been for a long time. But recently, influential critics have called for a ban.  

Responding to these calls, The Initiative’s new report, Class Divides: The impact of streaming on educational achievement and equality, explores both the local and international evidence on the educational effects of streaming.  

We found a lack of data on the prevalence of streaming in New Zealand schools. We know from PISA (Programme for International Student Assessment) data that it is widespread. But, the Ministry of Education doesn’t have specific information on which schools stream, how those that do stream go about it, or its effects in the New Zealand context.  

Critics argue that streaming exacerbates educational inequality. In New Zealand, they have claimed that it negatively affects Māori and Pasifika students, who are disproportionately placed in low streams. There is evidence that these critics have a point.  

Māori and Pasifika students are, unfortunately, frequently stereotyped as poor learners. Māori and Pasifika students placed in low streams can easily come to believe that the stereotype applies to them, as individuals.  

This phenomenon is known as stereotype threat. When students who are subject to negative stereotypes are placed in low streams, it can undermine belief in themselves as capable students. They can become demotivated and disengaged. In this way, a stereotype can become a self-fulfilling prophecy. But stereotype threat can be counteracted with clear learning goals and formative feedback. 

In favour of streaming, it is easier for teachers to pace instruction to students at similar stages of learning. That is particularly important in subjects like mathematics. For example, before students can understand fractions, they must thoroughly understand division. If prerequisite knowledge is not solidly learned before attempting to build on it, students can become overwhelmed and confused, and be left behind.  

Debate about streaming is often emotive. Proponents and critics alike have dug trenches.  The debate has been raging for over a century.  

In Class Divides, we argue that the evidence on streaming is more nuanced than those on either side of the polarised debate would suggest. Rather than a ban on streaming, our report calls for a systematic study of streaming in New Zealand’s classrooms. Schools could then retain, modify or abandon streaming in the light of evidence.