Children of non-English speakers need to be the ones removed from the mainstream classes so that they can get better instruction and so that they don't pull down native speakers and make them appear gifted.
Actually, I think that removing them would make it harder for them to learn English.
My DS10 went to a French immersion school for 4 years (pre-K to grade 2) and now goes to an after-school program for designed for native speakers. He didn't know any French when he started pre-K.
Through kindergarten, the teachers spoke nothing French to the kids for 80% of the day (it was 60% thereafter). They did French worksheets, played French games, and sang songs in French. All the non-Francophones spoke French pretty well by the end of kindergarten. The ones who stay through grade 5 are completely fluent. It's possible that overall IQs there might be a little higher than average, but I'm not sure.
I'm not sure how Spanish-speaking kids are taught English in most US public schools; I know that California doesn't allow bilingual ed. After the practice was outlawed in 1998 in large part because it allowed teachers to speak too much Spanish, Hispanic test scores
went up.
When ESL kids interact with English speakers in the classroom and on the playground, they learn lots of English --- just like my son learned French. The Hispanic kids I meet around here speak English with American accents. Some of them are very young (6 or 7; today I met some preschoolers speaking English to each other and Spanish to their parents).
Val
