The IDEA was first established in 1990. The act ensures that all students with disabilities have access to a free an appropriate education, meaning that they have the right to special services that allow them to receive their education. Before the act, there were no real laws that made an effort to include students with disabilities in the educational system. Thankfully, we've made progress since then.

6 Key Principles of IDEA
FAPE - Free and appropriate education - all students with disabilities have the right to an education that is tailored to their needs.

LRE - Least Restrictive Environment - Students with disabilities have the right to be educated in a classroom with peers without disabilities to the most appropriate extent. This means that the students with disabilities may remain in the classroom as long as they are still receiving the education that is most appropriate to their own circumstances.

Parent Participation and Shared Decision-Making - Parents are encouraged and have a right to participate in all decisions regarding their children. Parents must give consent even before a student is evaluated for an IEP. Parents attend meetings and challenge any decision related to the student.

Procedural Safeguards and Due Process - Procedural safeguards offer multiple options to resolve a disagreement if one were to arise between the school and the parents; one way is through a due process hearing. 

IEP - Individualized Education Program - A specific plan for a student that spells out his or her learning needs an documents the measures the school will take to meet those needs. The IEP also includes all of the progress from the time the student was evaluated to the current IEP plan.

Non - Discriminatory Assessment - Students who are considered for special education must be evaluated in a non-discriminatory way. For example, students must receive tests and evaluations in their primary language.

Check out this video for a quick rundown of the full history of IDEA.