I'm not a fan of immersion programs for language acquisition in and of itself. Many others have mentioned the benefits of self-selection bias in a public school setting as beneficial, which I don't deny.
However, I speak 3 languages fluently and another 2 at a basic level, and everything I learned was acquired in a language setting without subject extensions. From my personal experience, fluency is largely a function of practice over one's lifetime, which includes the ability to converse with native speakers.
A phased out immersion program seems problematic if the parents don't speak the immersion language themselves. The child could risk losing the language and have to relearn subject specific language in later years. Take me as an example-- my non-fluent languages are the ones that I didn't study into adulthood!
ETA: smacca's point about individual preferences over decoding vs. expressing complex thought is apt. My opinion is biased by my preference for the latter.
Last edited by aquinas; 12/17/12 10:25 AM.
