This week, colleagues and I published a paper looking at school selection in terms of genetics and GCSEs.
As you might expect, given these hot topics, this paper has received a lot of attention and there are many things to discuss, but here I want to focus on the things teachers can take away from this research.
Groups are made up of individuals
Because we divide students into groups (classes, sets, schools and school types), it’s easy to start thinking of them in this way: "the top-set students", "the private school kids" and so on. We can get into the habit of attributing outcomes to group membership (“Of course they did well, they were grammar school students”).
However, in our paper we found that the type of school that students attended (non-selective, grammar or private school) did not appear to make much of a difference to their GCSE results, once we accounted for the factors schools use in selection, both actively (such as ability on entrance tests) and passively (such as family socioeconomic status).
This may seem surprising considering the greater resources of private schools, or the competitive academic environments of grammar schools. But this research is a reminder that groups are merely individuals, selected on certain things.
When thinking about sets or schools or even school types, it’s also important to remember that there will be a lot of variation within the groups.
In our paper, we found that, although there were average exam score differences between school types, there was a lot of variation within school type – students getting low marks and students getting top marks. This is something you probably see in your own school and your own classes. But the students participate in the same lesson and they are attending the same school, so what are the drivers of these vast individual differences?
Genetics is important, too
Often teachers refer to the differences between students as environmental (support at home, behaviour in class), but genetics plays a role, too.
Decades of studies in behavioural genetics have shown that one of the biggest drivers of differences between students’ achievement is inherited DNA differences.
In our study, we created "genome-wide polygenic scores" by adding up tens of thousands of genetic variants in a person’s DNA that have been associated with educational attainment. We found these scores explain some of the individual differences in achievement and a small amount of the difference in GCSE grades between school types.
However, this is not to say that just because something is genetic, it is deterministic. Take learning to read. I could have many thousands of genetic variants linked to reading ability, but if no one teaches me to read, I’ll never learn.
So the general message for teachers is that students do differ, for a variety of reasons, some of these genetic, and we need to have a conception of students as fundamentally different and with different needs.
On a practical level, while student polygenic scores are not available to teachers, other student data is, and teachers should make use of this as much as possible to continue to differentiate effectively in their lessons.
And what about if and when polygenic scores are available? This is something all stakeholders in education should start discussing.
Emily Smith-Woolley is a PhD student in behavioural genetics at King’s College London