In Portugal, schools that perform better than the national and OECD average are those with a «healthy mix» of Portuguese and immigrant students, according to results extracted from the Programme for International Student Assessment (PISA) by Portuguese researchers Isabel Flores and David Justino. Looking at the 2015 PISA results in Mathematics, they found that the highest proportion of foreigners in a school should be 20% and the minimum should be 1%.
In schools where there is no diversity or a too high concentration of foreigners, students may have a delay of more than a year in learning compared to pupils in the rest of the country. Note that the average percentage of immigrant students in Portugal is around 10% – including the so-called first-generation immigrants (born abroad from foreign parents) and second-generation immigrants (born in Portugal from immigrant citizens).
The researchers have also highlighted that an accumulation of factors – being an immigrant, not feeling integrated and not speaking Portuguese at home – creates «outbreaks of discrimination». They therefore suggest schools to teach Portuguese to parents so that they can practice at home with their children and other activities to reinforce pupils’ sense of belonging.
European Website on Integration