Cal. Educ. Code § 48900.4

In addition to the grounds specified in Sections 48900 and 48900.2, a pupil enrolled in any of grades 4 to 12, inclusive, may be suspended from school or recommended for expulsion if the superintendent or the principal of the school in which the pupil is enrolled determines that the pupil has intentionally engaged in harassment, threats, or intimidation, directed against school district personnel or pupils, that is sufficiently severe or pervasive to have the actual and reasonably expected effect of materially disrupting classwork, creating substantial disorder, and invading the rights of either school personnel or pupils by creating an intimidating or hostile educational environment.