34 C.F.R. § 300.131
(b) Child find design. The child find process must be designed to ensure—
(f) Out-of-State children. Each LEA in which private, including religious, elementary schools and secondary schools are located must, in carrying out the child find requirements in this section, include parentally-placed private school children who reside in a State other than the State in which the private schools that they attend are located.
(Approved by the Office of Management and Budget under control number 1820-0030)
(Authority: 20 U.S.C. 1412(a)(10)(A)(ii))