(a) General. A public agency must ensure that a reevaluation of each child with a disability is conducted in accordance with §§ 300.304 through 300.311 -
(1) If the public agency determines that the educational or related services needs, including improved academic achievement and functional performance, of the child warrant a reevaluation; or
(2) If the child's parent or teacher requests a reevaluation.
(b) Limitation. A reevaluation conducted under paragraph (a) of this section -
(1) May occur not more than once a year, unless the parent and the public agency agree otherwise; and
(2) Must occur at least once every 3 years, unless the parent and the public agency agree that a reevaluation is unnecessary.