Ed. Code, § 44811

(a) Any parent, guardian, or other person whose conduct in a place where a school employee is required to be in the course of his or her duties materially disrupts classwork or extracurricular activities or involves substantial disorder is guilty of a misdemeanor.

(b) A violation of subdivision (a) shall be punished as follows:

(1) Upon the first conviction, by a fine of not less than five hundred dollars ($500) and not more than one thousand dollars ($1,000), or by imprisonment in a county jail for not more than one year, or by both the fine and imprisonment.

(2) Upon a second conviction, by imprisonment in a county jail for a period of not less than 10 days, and not more than one year, or by both imprisonment and a fine not exceeding one thousand dollars ($1,000). The defendant shall not be released on probation, or for any other basis until he or she has served not less than 10 days in a county jail.

(3) Upon a third or subsequent conviction, by imprisonment in a county jail for a period of not less than 90 days, and not more than one year, or by both imprisonment and a fine not exceeding one thousand dollars ($1,000). The defendant shall not be released on probation, or for any other basis until he or she has served not less than 90 days in a county jail.

(4) Upon a showing of good cause, the court may find that for any mandatory minimum imprisonment specified by paragraph (2) or (3) of this subdivision, the imprisonment shall not be imposed, and the court may grant probation, or the suspension of the execution or imposition of the sentence.

(c) This section shall not apply to any otherwise lawful employee concerted activity, including, but not limited to, picketing and the distribution of handbills.