I've noticed this varies by schools.
The following is from this government website, note A and 3
https://www2.ed.gov/policy/elsec/leg/esea02/pg2.html
Section 1115 Targeted Assistance Schools
Scroll up to get school wide
(A) IN GENERAL- Children who are economically disadvantaged, children with disabilities, migrant children or limited English proficient children, are eligible for services under this part on the same basis as other children selected to receive services under this part.
(B) HEAD START, EVEN START, OR EARLY READING FIRST CHILDREN- A child who, at any time in the 2 years preceding the year for which the determination is made, participated in a Head Start, Even Start, or Early Reading First program, or in preschool services under this title, is eligible for services under this part.
(C) PART C CHILDREN- A child who, at any time in the 2 years preceding the year for which the determination is made, received services under part C is eligible for services under this part.
(D) NEGLECTED OR DELINQUENT CHILDREN- A child in a local institution for neglected or delinquent children and youth or attending a community day program for such children is eligible for services under this part.
(E) HOMELESS CHILDREN- A child who is homeless and attending any school served by the local educational agency is eligible for services under this part.
(3) SPECIAL RULE- Funds received under this part may not be used to provide services that are otherwise required by law to be made available to children described in paragraph (2) but may be used to coordinate or supplement such services.