Tex. Educ. Code § 55.22

All revenue bonds heretofore approved by the attorney general and registered by the comptroller, which were issued, sold, and delivered by any board, and which are payable from or secured by a pledge of any revenues, income, receipts, or other resources of such board, are hereby validated in all respects, together with all proceedings authorizing the issuance thereof, and said bonds and proceedings are and shall be valid and binding obligations in accordance with their terms and conditions for all purposes, as though they had been duly and legally issued and authorized originally.