Campbell may have a point about the constitutional free speech protections held by students, but there IS a supreme court backed decision that limits student's speech. This summary is succinct: "A student’s speech... may not be censored... unless it is reasonably clear that it will ignite significant disruption or collide with the legal rights of others."
Of course, the devil is in the term "reasonably clear" that it will invite "significant" disruption. Does hate speech meet this criteria? And what is hate speech? For example, students are known to say "I hate you." What if they say "I hate Blacks"?  Or use the "N" word. (yes, being sensitive or politically correct here).
Balderas was taking a stand that could be interpreted as too extreme. But until his expectation is tested in a case and found to be without merit, there is no harm and no foul.