Does multilingualism protect against socioeconomic disadvantage in children's educational attainment?

It is well-established that there is a substantial attainment gap between children and young people who are, and are not, eligible for free school meals (FSM). This so-called "disadvantage gap" has stubbornly remained despite government interventions and additional funding. However, we know less about the possible protective factors that may guard against low attainment in children who receive FSM. In particular, government data suggests that children who speak English as an additional language (EAL) show a much smaller disadvantage gap than children who speak only English, and it appears that this varies with home language and with ethnicity. There are a number of reasons why speaking more than one language may result in better educational attainment. First, there is some (controversial) evidence that multilingual speakers gain cognitive benefits from switching between languages and these lead to better learning and hence better school outcomes. Second, there may be household variables (parental education, parental engagement with school, expectations in the home about education and careers) that influence outcomes, and these may be more common in certain types of families (recent immigrants, certain ethnic or linguistic communities).

The administrative datasets, Longitudinal Education Outcomes (LEO) and Growing Up in England Dataset will be used to ask the following questions:
To what extent does EAL status act as a protective factor from socioeconomic disadvantage in educational attainment?
Which (if any) language backgrounds are particularly helpful and does language background interact with ethnicity and other factors (household information)?
Which measures of early school attainment are most predictive of success at GCSE, A-Level, further and higher education, and career success?
Answering these questions will increase understanding of the protective and risk factors for academic and employment success for those born into socioeconomic disadvantage.