The title of the OP is slightly misleading, probably in an effort to make the issue broader than it really may be.
White students are no longer a majority in PUBLIC schools.
While this certainly has something to do with birth rates and illegal immigration of Hispanics, it also has something to do with homeschooling and private schooling being more available. Free accredited Online Education is becoming a more popular option for whites while Free and Reduced Lunches are a more popular option for Hispanics.
Online Free Burritos are not very nutritious.
Rather than multiculturalism, this is an indication of some massive resegregation. Public schools will become de facto nonwhite, and soon non Asian as well. A side effect will be, those without children in public schools will not be very likely to vote for increased funding for public schools, nor for politicians that support increased funding.