Bilingual children appear to be happier : Studies show that bilingual children show more empathy and are apparently happier in school.

Bilingual children appear to have better academic results : Studies show that bilingual children are ahead in standardized reading tests at the end of middle school. They have higher test scores in general and show early understanding of grammar systems and have extended vocabularies.

Bilingualism appears to confer long term benefits : Studies show that bilingual children have a higher earning potential. Bilingualism also appears to decrease cognitive decline and the risk of dementia.

Studies also show that it's important to start early :

Starting a dual-language program from an early age confers the advantage of reinforcing the value of both languages. Language is a vehicle of both culture and values. Dual language programs reinforce the vision that both languages, as well as the culture and values they represent, are of equal value.

Bibliography

Kroll, Judith F., and Ellen Bialystok. "Understanding the consequences of bilingualism for language processing and cognition." Journal of Cognitive Psychology 25.5 (2013): 497-514.

Bialystok, Ellen, Fergus IM Craik, and Gigi Luk. "Bilingualism: consequences for mind and brain." Trends in cognitive sciences 16.4 (2012): 240-250.

Bak, Thomas H., Mariana Vega-Mendoza, and Antonella Sorace. "Never too late? An advantage on tests of auditory attention extends to late bilinguals." Frontiers in psychology 5 (2014): 485.

Steele, Jennifer L., et al. "Effects of dual-language immersion programs on student achievement: Evidence from lottery data." American Educational Research Journal 54.1_suppl (2017): 282S-306S.

Genesee, Fred. "What do we know about bilingual education for majority language students." Handbook of bilingualism and multiculturalism 547 (2004): 576.

Deussen, Theresa, et al. "The impact of Project GLAD on fifth-grade literacy: Sheltered instruction and English learners in the mainstream classroom." annual meeting of the American Education Research Association, Chicago, IL. Retrieved November. Vol. 27. 2015.

Bialystok, Ellen. "Reshaping the mind: the benefits of bilingualism." Canadian Journal of Experimental Psychology/Revue canadienne de psychologie expérimentale 65.4 (2011): 229.

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