(a) Each board of trustees in each school district within the state may adopt rules for reasonable forms of punishment and disciplinary measures. Subject to such rules, teachers, principals, and superintendents in such district may impose reasonable forms of punishment and disciplinary measures for insubordination, disobedience, and other misconduct. (b) Teachers, principals and superintendents in each district shall be immune from civil and criminal liability in the exercise of reasonable corporal discipline of a student as authorized by board policy.