Does speaking more than one language help or hinder learning and outcomes at school? This is a surprisingly challenging area of research, with many different factors involved. There is no simple answer, and much more research to be done.
The question of whether bilingualism (and multilingualism) presents a cognitive advantage or disadvantage at school is hugely interesting for parents, teachers, and researchers. With rising numbers of pupils in the UK speaking more than one language, many are keen to know the possible impact on learning.
Much of the research into bilingualism focuses on executive functions. These are the skills that allow us to hold and manipulate information in mind, stop automatic responses, and switch between tasks or mental states. Being able to speak more than one language appears to rely heavily on these executive function skills and it is easy to see how.
For example, a bilingual child may have to translate sentences, holding lots of words in their mind at once. They may have to stop their automatic response to speak in one language when another language is appropriate in a given scenario. They may have to switch between languages regularly, perhaps doing homework in one language while speaking to their family in another. Research has therefore considered whether bilingualism leads to enhanced executive function skills, since bilinguals are seemingly getting a great deal of practice.
The possibility of enhanced executive functioning is an exciting prospect, since executive functions are known to associate with measures of academic performance. Not only would this mean that bilingual children are at an advantage, but the implications might go further. Perhaps schools would be encouraged to teach languages from a younger age, to enable these positive impacts to take effect in those who aren’t from a bilingual home.
Carrying out scientific research to examine these possible effects is incredibly challenging, and the area has become controversial. While some research suggests that executive functions are indeed better in bilingual children, this is not the case across the board, with other research finding no differences in executive function. But even if it was widely accepted that bilingual children had better executive functions, it does not necessarily follow that they would perform better at school.
It was previously hoped that executive function training would lead to better academic outcomes, and attempts at this have largely shown that executive functions can be trained (for instance through computer games) but that this does not have wider impact on attainment. Bilingual children may therefore be getting lots of training in executive functions, and may be very good at using them in the context of languages, but they may not be any better equipped to apply executive functions to other contexts (like maths or science learning).
“Even if it was widely accepted that bilingual children had better executive functions, it does not necessarily follow that they would perform better at school.”
There are other important factors that are relevant here. Bilingualism can be associated with socioeconomic status. For example, bilingual children in a certain region might tend to be from richer families than monolingual children. If a study finds that being bilingual is related to executive function ability, this could be partially driven by socioeconomic status. There may also be effects according to the specific languages that the child speaks – some languages are easier to learn than others; some pairs of languages are more similar than others. All of this makes it very difficult to make any firm conclusions about the effects of bilingualism.
While the evidence around growing up bilingual continues to increase, it is important to bear in mind the challenges in this research, and to be cautious when reading about the purported effects. An understanding of how the number of languages spoken impacts upon learning remains a fascinating area for ongoing research. But for the time being, perhaps we should appreciate the most obvious known benefit of speaking more than one language: that is, being able to speak more than one language!