34 CFR § 300.520 - Transfer of parental rights at age of majority.
(a) General. A State may provide that, when a child with a disability reaches the age of majority under State law that applies to all children (except for a child with a disability who has been determined to be incompetent under State law)—
(1)
(i) The public agency must provide any notice required by this part to both the child and the parents; and
(ii) All rights accorded to parents under Part B of the Act transfer to the child;
(2) All rights accorded to parents under Part B of the Act transfer to children who are incarcerated in an adult or juvenile, State or local correctional institution; and
(3) Whenever a State provides for the transfer of rights under this part pursuant to paragraph (a)(1) or (a)(2) of this section, the agency must notify the child and the parents of the transfer of rights.
(b) Special rule. A State must establish procedures for appointing the parent of a child with a disability, or, if the parent is not available, another appropriate individual, to represent the educational interests of the child throughout the period of the child's eligibility under Part B of the Act if, under State law, a child who has reached the age of majority, but has not been determined to be incompetent, can be determined not to have the ability to provide informed consent with respect to the child's educational program.