Tex. Education Code § 51.925

(a) An institution of higher education may not discriminate against or penalize in any way a member of the faculty of the institution who is absent from work for the observance of a religious holy day and gives proper notice of that absence if the customary and generally applicable educational practices of the institution permit general personal absence by members of the faculty. If personal absence is customarily penalized, the penalty for absence due to observance of a religious holy day under this section shall be forfeiture of one day's pay equivalent for each day of absence.

(b) In this section, "institution of higher education" has the meaning assigned by Section 61.003 of this code, except that the term includes the Southwest College for the Deaf and Texas State Technical College System.

(c) In this section, "proper notice" means that the faculty member shall provide a listing of religious holy days to be observed during the semester to the chairman of the department and shall provide notice of such days in advance to all students whose class would be canceled due to the faculty member's absence. Notice herein shall be in writing and shall be personally delivered to the chairman of the department, receipt therefor being acknowledged and dated by the chairman, or by certified mail, return receipt requested, addressed to the chairman.

(d) In this section, "religious holy day" means a holy day observed by a religion whose places of worship are exempt from property taxation under Section 11.20, Tax Code.