Relating to public school accountability and actions and other proceedings challenging the operations of the public school system.

HB 2866 amends Texas education law to refine public school accountability systems. It requires assessment tools to be validated as "valid and reliable" by an independent entity before use, limits school district appeals of commissioner decisions to cases where the district is directly aggrieved, and updates how school performance is evaluated using data from the PEIMS system and student assessments. The bill directly affects Texas public school districts, campuses, and the commissioner of education by changing how accountability measures are implemented and challenged. Key provisions include new validation standards for tests, revised appeal procedures, and expanded requirements for evaluating district programs using specific data sources.