In Miller v. California (1973), the Supreme Court affirmed its holding in Roth v. United States (1957) that obscenity was not protected by the First Amendment. In Rosario v. Clark County School District (2013), a school district attempted to justify the sanctions for off-campus student speech under Miller. This chapter first discusses pertinent Supreme Court cases relating to obscenity, culminating with the Miller case. Next, this chapter discusses how a school district attempted to censor off-campus student speech as obscenity in the Rosario case.