In AISD, I don't know if kids who speak Spanish only can graduate. I'll have to check that out w/ my teacher connections. However, as I said earlier my wife spoke in English in her high school ESL Social Studies class but the kids responded in English. However, (I freelance as a photographer) I have been in East side schools in Austin (ie. high minority/immigrant Low SES) and I've heard more Spanish than English. The program that I photograph was presented in Spanish with an English translator. Depending on the classes, sometimes they didn't need the English translator. I'm just throwing this out there - but what happens to the ESL kids in middle school, high school. Again, I base this on my personal observation - the classes are there but I don't hear it in the hallways. As you said, Anse, the immigrants kids and parents mostly want to learn English. There are exceptions, I'm sure.
Funny about your comment about your uncle... I have a niece-in-law who was from the valley - blond, blue-eyed, German descent, who speaks very good Spanish. Better than my nephew (her husband) and his brother. The valley is so close that you might as well be in Mexico.
But I thought the original issue was about the black kids and mexican kids fighting. To me, the issue is the language barrier. I remember attending some class at the LBJ School of Public Affairs (building future leaders of something like that...). The class was open to all however, most of the attendees were hispanic. The one or two black people that attended dropped out because, "I/we don't want to hear you all speak that 'meskin'"
so the race wars continue...