child
(6) Except as used in section 1786 of this title , the terms “child” and “children” as used in this chapter, shall be deemed to include persons regardless of age who are determined by the State educational agency, in accordance with regulations prescribed by the Secretary, to have 1 or more disabilities and who are attending any nonresidential public or nonprofit private school of high school grade or under for the purpose of participating in a school program established for individuals with disabilities.