Education Code §37.122

(a) A person commits an offense if the person possesses an intoxicating beverage for consumption, sale, or distribution while: (1) on the grounds or in a building of a public school; or (2) entering or inside any enclosure, field, or stadium where an athletic event sponsored or participated in by a public school of this state is being held. (a-1) It is a defense to prosecution under this section that the person possessed the intoxicating beverage: (1) at a performing arts facility; and (2) during an event held outside of regular school hours and not sponsored or sanctioned by a school district. (b) An officer of this state who sees a person violating this section shall immediately seize the intoxicating beverage and, within a reasonable time, deliver it to the county or district attorney to be held as evidence until the trial of the accused possessor. (c) An offense under this section is a Class C misdemeanor.