Final answer:
The legislative act addressing education for children with disabilities, mandating free and appropriate education in the least restrictive environment, and requiring state EI programs is the Individuals with Disabilities Education Act (IDEA).
Step-by-step explanation:
The legislative act that provides for free and appropriate education for children with disabilities in the least restrictive environment and includes requirements for the states to develop EI programs is best identified as the Individuals with Disabilities Education Act (IDEA). In 1975, it was originally passed as the Education for All Handicapped Children Act, mandating that public schools educate all children with disabilities. This act has undergone various revisions, notably in 1990 when it was renamed IDEA, which expanded the rights and protections for children with disabilities and their families within the school system.
IDEA emphasizes the importance of individualized education programs (IEPs) to ensure that students with disabilities receive tailored and effective education, as well as the necessity of educating them in the least restrictive environment possible. The act also gives parents the opportunity to participate in their children's education planning and decisions. Along with IDEA, other federal initiatives like the Rehabilitation Act of 1973 and the No Child Left Behind Act have also contributed to the advancement of educational opportunities for students with disabilities.