Which guaranteed students with disabilities a “free appropriate public education” in an environment that was not restrictive?

Free Appropriate Public Education for Students with Disabilities, Requirements Under Section 504 of the Rehabilitation Act of 1973.

https://www2.ed.gov/about/offices/list/ocr/docs/edlite-FAPE504.html

Section 504 of the Rehabilitation Act of 1973 guaranteed students with disabilities a Free Appropriate Public Education.

Free Appropriate Public Education (FAPE) constitutes an educational right of all children in the United States that is guaranteed by the Rehabilitation Act of 1973 and the Individuals with Disabilities Education Act (IDEA).  

Under Section 504, FAPE is defined as, "...the provision of regular or special education and related aids and services that are designed to meet individual needs of handicapped persons as adequately as the needs of nonhandicapped persons are met and are based on adherence to procedures that satisfy the requirements of the section."(quote)

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