Nolo's Plain-English Law Dictionary

Least Restrictive Environment

A requirement of the Individuals with Disabilities Education Act that school districts place disabled children in the classroom setting that best meets their individual needs, rather than automatically assume that a special class or school is the best option. In many cases, the least restrictive environment, or LRE, is a regular classroom with nondisabled children (also known as mainstreaming), with additional services provided to help the disabled child succeed at school.
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