http://www.cast.org/index.html

The concise definition of Universal Design for Learning found below was provided by the Higher Education Opportunity Act of 2008. 

The term UNIVERSAL DESIGN FOR LEARNING means a scientifically valid framework for guiding educational practice that:

(A) provides flexibility in the ways information is presented, in the ways students respond or demonstrate knowledge and skills, and in the ways students are engaged; and

(B) reduces barriers in instruction, provides appropriate accommodations, supports, and  challenges, and maintains high achievement expectations for all students, including students with disabilities and students who are limited English proficient.

Three principals act as guidelines for Universal Design for Learning:

Principle I: Provide Multiple Means of Representation (What are we learning?)

Principle II: Provide Multiple Means of Action and Expression (How will I show you?)

Principle III: Provide Multiple Means of Engagement (Why are we learning?)