What is behind the achievement gap between poor Asian and Latino students?

[RandySF]

My son attends a wonderful school is the San Francisco Unified School District located where Nob Hill, Tenderloin and Upper Polk Street neighborhoods meet. As a result, most of the kids come from economically disadvantaged households where another language is spoken. The largest single ethnic group is Asian followed by Latino. Test scores show the Asian students overwhelmingly score at or above proficiency in math and English while Latinos score well below. I've spent the school year trying to figure out the root causes and still cannot figure it out. But I have ruled out a number of factors for the following reasons:

- Economics: Most of the Asian AND Latino students come from immigrant backgrounds who are struggling to get on their feet. Either they were born somewhere else or their parents arrived within the past several years. They tend to live in the Tenderloin and Polk.

- English as second language: Same as above.

- Parental involvement: I refuse to believe that parents of any one background are less involved than others.

Any suggestions?