Immersion programs have taught math in French for close to forty years and research has demonstrated that French immersion students match or surpass the math achievement of their peers in the English program.
French Immersion students learning math in French achieve higher scores on standardized tests of mathematical ability than those of French Immersion students taught math in English. [Bournot-Trites, M., Reeder, K. (2001); Barik, H., Swain, M. (1978); Barwell, R. (2010); British Columbia Ministry of Education, (2000); Dicks, J., et al (2008); Dube, L., MacFarlane, A. (1991); New Brunswick Dept. of Education (2000); Turnbull, M., Hart, D., Lapkin, S. (2003)]
Language skills learned in the second language are transferred to the first language, and vice versa. French Immersion students who study math in French in intermediate years are not handicapped when they switch to math taught in English at high school [Bournot-Trites, M., Reeder, K. (2001)].
French Immersion students who studied subjects in French in high school had no trouble studying them in English at post-secondary level. [Canadian Parents for French (2005)]
There is no evidence that learning a second language somehow overtaxes the brain of learners and interferes with learning in other ways. Rather, a second language enhances cognitive functioning, especially “executive control” – the decision-making centre of the brain. More students are schooled in their second language in the world than in their first language. (Bialystok, 2001; Baker, 2012; Cummins, 2000)
Additionally, there is mounting evidence that students who undertake the challenge of second language learning also improve their competencies in organization, resiliency and openness to others, ie: different cultures, religions, lifestyles.
Please find attached a link to the latest research on the benefits of Second Language Learning
https://www.caslt.org/files/pd/resources/research/Lit-review-Impact-L2-Learning-Exec-Summary.pdf
It's obvious that knowing more than one language can make certain things easier — like traveling or watching movies without subtitles. But are there other advantages to having a bilingual (or multilingual) brain? Mia Nacamulli details the three types of bilingual brains and shows how knowing more than one language keeps your brain healthy, complex and actively engaged. Watch her Ted Talk below.
https://www.ted.com/talks/mia_nacamulli_the_benefits_of_a_bilingual_brain?language=en