This is a very important and timely question as many parents are now making final decisions for where to enroll their children next fall. My quick answer is “yes” it is an extremely effective method of learning a new language. I also think that it is a very effective method for learning in general. Here is why. It is language learning while doing. Immersion classrooms have to be highly engaging, project based classrooms where language is the medium of instruction, rather than the exclusive focus of instruction (Krashen, 1999). Regarding class size, from my own observations of my daughter’s Spanish immersion classroom, my observations of other immersion classrooms in other schools here in Arizona and around the country, and from observing my own classroom as an immersion teacher in the past, I can say that the dynamics of a classroom with 29-30 students in an immersion setting compared to a non-immersion setting can be quite different. I think this can be attributed to many factors, but I’ll highlight four here.
1) Students are challenged in a different way in immersion programs and this challenge can, and many times does, elicit more attention and greater focus. Check out the work of Ellen Bialystock on the benefits of bilingualism (here’s one of her most recent articles: Bialystok, E. (2011). Reshaping the mind: the benefits of bilingualism. Canadian Journal of Experimental Psychology/Revue canadienne de psychologie expérimentale, 65(4), 229.)
Bialystok points to how learning in two languages develops both language systems in the mind and that working your brain muscle in school is analogous to working out other muscles at the gym. This brain exercise can lead to greater lifetime functioning of the executive control system which can lead to greater abilities to focus attention, ignore distractions, trouble shoot and manage complex tasks. Really cool evidence of this happening in children in immersion programs is when they code-switch or use two languages in the same conversation or even in the same sentence (e.g. “At school today we sang una canción about números y colores.”)
2) Another related reason why often times we observe large immersion classes on task and focused has to do with what De Jesus (2009) calls the “cognitive stretch.” Here is one of his articles: DeJesus, S. C. (2008). AN ASTOUNDING TREASURE: DUAL LANGUAGE EDUCATION IN A PUBLIC SCHOOL SETTING. Centro Journal, 20(2).
This sustained focus to understand and make sense of content in another language, by watching the teacher’s facial expressions, gestures, and use of realia, forces students to learn to pay attention and focus and stretch their current cognitive abilities to more advanced thinking.
3) Perhaps the most important factor that adds to the effectiveness of dual language immersion programs on language and content learning is what the students say themselves: It’s not boring. It keeps them on their toes, and is fun. Many students also develop a sense of pride pretty early on with becoming bilingual and being a part of something different and special at school.
4) This leads to the last factor that I will highlight here. Since these dual language immersion programs are special islands within the larger school setting, they get a lot of attention by teachers, school and district administrators, as well as very involved parents. This attention is good and helps to ensure that these programs, even if they have large class sizes from time to time, are successful.
Bialystok, E. (2011). Reshaping the mind: the benefits of bilingualism. Canadian Journal of Experimental Psychology/Revue canadienne de psychologie expérimentale, 65(4), 229.)
DeJesus, S. C. (2008). AN ASTOUNDING TREASURE: DUAL LANGUAGE EDUCATION IN A PUBLIC SCHOOL SETTING. Centro Journal, 20(2).
Krashen, S. (1999). Seeking a role for grammar: A review of some recent studies. Foreign Language Annals, 32, 245-257.