race, ethnicity, and a strong American dislike for immigrants in general.  These parents probably thought that they were protecting their children from all of this.

Third, these students were living in a gang culture. Gang affiliations were based on race, ethnicity, and neighborhood.  To show allegiance to their respective gangs, they could not mingle with those from other gangs. You may have seen the film West Side Story, which, for Hollywood, is a fairly accurate representation of this world, although none of Gruwell's students were breaking into song at dramatic moments. 

Finally, all of these students had good reason to avoid white people in the education system. It took a long time for Gruwell to gain these students' trust.  Teachers and administrators had consistently let them down, with neglect, low expectations, prejudice, and even cruelty. It is not at all surprising that they had no reason to think well of white people.

It is a remarkable testament to Gruwell's powers as a teacher that students, having led such lives, could place their trust in her, enough to even make them care about the problems of others, not just their own problems.  It is their engagement over the Holocaust that turns them into empathetic people, and it is this that allows them to get past all of the limitations that they have had all their lives, limitations created by their environment. 

The simple answer to this question is that they don't know any better. Just think what kind of backgrounds these students come from, what kind of lives they've been leading. For the most part, they've spent the whole of their short lives in neighborhoods where just about everyone comes from the same ethnic group. Growing up in such an environment inculcates a certain mindset which encourages racial solidarity as a social solvent that keeps people together in the face of hostility from the outside world. This mindset is so deeply ingrained that it becomes hard for the kids to break free from it. That's why Erin has her work cut out if she's going to teach her students the overriding importance of freedom. By blindly sticking to their own kind, the kids are not truly free; they're the prisoners of their own environments and the exclusive mentality they've created and sustained.

Interesting question! In the book The Freedom Writers many of the students are unwilling to associate with other students from different ethnic or racial backgrounds.

Throughout the book, students comment about their unwillingness to associate with others from different backgrounds. Although many of the students find this behavior in others (such as during their reading of Shakespeare’s Romeo and Juliet) to be wrong or illogical, they find the segregation to be normal with themselves.

In the book, several of the students express that blending the different backgrounds into one classroom seems problematic. Many of the students segregate during lunch. This appears normal to many of the students. As one student reveals:

“This school is just asking for trouble when they put all of these kids in the same class. It’s a disaster waiting to happen.”

Although there are numerous different explanations about this intolerance, there are some particularly noteworthy causes. As some students illustrate, the segregation has existed for years; thus, change seems unlikely. Furthermore, many of the students do not believe they can cause a change of such magnitude. Others appear scared of upsetting their parents. Lastly, violence instills this separation as well.

Consequently, segregation is commonly seen in this book. Throughout the story, students begin to question the intolerance. However, several factors encourage their unwillingness to associate, such as violence and fear.

The "unteachable" students that Erin tries to reach don't have much in life. For the most part they're poor and live in tough neighborhoods where gang violence is rife. About the only thing they do have is racial solidarity; it provides a kind of stability to otherwise unstable lives. The students have grown up in areas which are generally segregated by race; it's pretty much all they know. So the very idea of associating with those from other racial groups is potentially scary as it forces the students to step outside their comfort zones, to engage with the wider world outside their ethnic enclaves.

That's why it's so important for Erin to get the kids to broaden their horizons a little, to realize that separating oneself into a distinct racial group fosters mutual loathing and suspicion. It's only by learning this valuable lesson that the kids can begin to understand the true nature of freedom and how that freedom is severely compromised by their failure to associate with those of different racial groups.

In order to understand the answer to this question, it is equally important to understand the cultural context of the question itself. Essentially, the Freedom Writers' novel is based in California, where gang mentalities are rampant. Often times, the gang mentality dictates that you hate rival gangs and even attempt to kill them if given the chance. For this reason, many of the students who are portrayed in the novel did not have a love or understanding of their fellow classmates. In fact, they despised their fellow classmates and did not want to learn with or about them.

Social psychology explains that this mentality is a protective mechanism for the in-group bias. This means anyone who does not fit the mold of the in-group is characterized, often times negatively, to adjust for preconceived notions about them. Learning with and from those that a cultural group does not understand will often fly in the face of commonly held beliefs about that group. To that end, the learning never takes place out of fear and ignorance.