The protection provided against a violation of § 6–902 of this subtitle shall apply only if: The public school employee has a reasonable, good faith belief that the public school employer has, or still is, engaged in an activity, a policy, or a practice that is in violation of a law, rule, or regulation; The public school employee discloses information that the employee reasonably believes evidences: An abuse of authority, gross mismanagement, or gross waste of money; A substantial and specific danger to public health or safety; or A violation of law; and The public school employee has reported the activity, policy, or practice to a supervisor or an administrator of the public school employer in writing and afforded the employer a reasonable opportunity to correct the activity, policy, or practice.