When I studied for my teaching degree in English about 15 years ago, I once had to get informed on the effect of bilingualism on academic achievement. I remember reading a great variety of texts, some of them arguing that bilingual children were disadvantaged compared to monolingual children, most others, especially the more recent ones, saying the opposite. The prevailing idea was that bilingualism didn’t have any negative effects on intelligence and academic achievement, but not everybody seemed to be convinced.

Now that Scarlett finished her first year of primary school and brought home her first end-of-term-report, I wondered again what today’s scientific view on multilingualism and academic achievement is. So far Scarlett has been doing really well in school. She loves going to school and got very good marks. Her teachers are happy about her and say that her Italian language skills are good.

My internet research quickly showed that in the last decades a lot of scientific research on the topic has been done. Typing search terms like “bilingualism and intelligence” brings a great quantity of results. I read some of them and found they were quite well summarised in a 2012 New York Times article “Why Bilinguals Are Smarter” and the Wikipedia article “Cognitive advantages of bilingualism”. Looking at the history of scientific research I also understood why 15 years ago I still got such a mixed impression. Up to the 1960s the scientific literature agreed that bilingualism had a negative effect both on the strong language and on the general cognitive development. These studies later proved to be methodologically flawed and new research showed that bilingual children benefit both from a linguistic and a cognitive point of view.

Today the generally agreed opinion is that bilingual children perform better in languages as they develop a better meta-linguistic awareness. They are able to better analyse the structures of languages and they gain a greater awareness of the meaning. On a cognitive level bilingual children benefit from a heightened ability to monitor the environment and to suppress information that is not important. On average they achieve higher results in the so called “executive functions” which means processes such as problem solving, mental flexibility, attentional control, inhibitory control, and task switching. Research also suggests that bilinguals are more creative than their peers, it seems, for example, that they are better in story telling.

But what about trilingual children? Are they even better in meta-linguistic awareness and in executive functions? I couldn’t find any major comprehensive studies, maybe because research on trilinguals is too young.  The problem starts with the definition of what a trilingual speaker is. With bilinguals one important factor is balanced bilingualism. Only if you speak both languages on a high level (being able to participate in a classroom) positive effects can be shown. With trilingual speakers usually there is at least one language that is weaker than the others.

I found some articles that said being trilingual doesn’t give you much advantage over a bilingual speaker. The decisive factor, it was argued, is that you learn to focus on the right language even if there is another one competing. They argue it does not change much whether there are one or two languages competing. There are however studies that suggest a cognitive advantage of trilingual speakers when it comes to highly complex tasks.

Also on a language level there is little scientific evidence. If knowing two language systems gives you a better understanding of languages, then knowing three languages should give you an even better understanding. Or does it simply confuse you? So far no scientific answer.

From my personal non-scientific experience I got the impression that being trilingual correlates with good academic achievement. Working in a bilingual school I have had quite some trilingual children over the past years and they were usually good or excellent students. They were usually very good in their strongest language and also in the others they reached a very high level.

But I suppose that here we are facing the chicken-egg-question. I am talking about almost balanced trilingual speakers. These students might not be clever because they are trilingual, they might be truly trilingual because they are clever. Check this blog in fifteen years time and I might be able to tell you what the scientific truth is.