Inquiry - Bilingual, ESL programs

For my inquiry project, I'm interested in researching bilingual education programs and ESL programs. Through externships and Praxis placements, I've been able to observe different classrooms that revolved around a bilingual classroom system. One was in second grade classroom where the students' native language was Spanish and the teacher (who was Latina American and could identify with her students' backgrounds) actively used Spanish in her lessons. Another was in a middle school classroom where the students were primarily Haitian immigrants, and the teacher (of a Caucasian Jewish American background) had knowledge of French but didn't really use it in the classroom, and there appeared to be a large disconnect between her and the students. 

I've always wondered about these programs from different points of view. I just have a lot of questions.

For the students who are in these language programs --- do they feel welcome in the school? Do they feel separated and “different” from the mainstream students, and what happens when they are placed into mainstream classrooms? Do they feel as though their native languages and cultures are respected? Are their programs providing enough support for them? 

For the teachers in these classrooms --- what kind of training and requirements do they pursue before they go down the ESL path, and does this training include preparation for multicultural education? What is it like for teachers who can speak their students' native language vs teacher's who have little or no knowledge of their students' native language? What is it like in classrooms where there are multiple native languages used? What are the challenges that arise from preparation for standardized tests?

For the communities which have schools with large ESL student populations--- what are the types of interactions between these student populations and the larger community? Are there people or organizations(connected to or separate from the schools) that work to serve the ESL student population?