UDL and differentiated instruction are, without a doubt, similar concepts that share many of the same goals, ideas about learning, and even classroom practices. However, that is not to say that they are synonymous. The two differ in a few key aspects of their guiding principles, although I believe that they can work together and complement one another in a successful classroom.
Both approaches share a common end goal: to help all students to learn and achieve the most they possibly can. Both UDL and differentiated instruction believe that students should not all be forced to fit into the mold of a single, inflexible curriculum. Rather, they believe that instruction should be adjusted in order to accommodate all students. They have high expectations for all students and embrace student differences. Therefore, the learning environments in both approaches include a lot of support and appropriate amounts of scaffolding. In addition, they both place an emphasis on the fact that individual students learn in different ways, and that each student needs to be given the opportunities to learn in ways that work best for him/her and are at an appropriate level.
However, the two approaches differ a bit in the ways in which they go about achieving this. Differentiated instruction places a lot of emphasis on formative assessments, which make the basis for many instructional decisions. The key here is to be constantly assessing students, determining what they need, and then adjusting instruction in order to meet those needs. As a result, teachers are constantly making changes as they go in response to student needs. UDL looks at this adjusting of instruction in a different way. When an architect is designing a building, he/she does not wait for someone in a wheelchair to try to access the building before installing a ramp. Rather, the architect anticipates that someone in a wheelchair will need to access the building and includes the ramp in the original design. Universal design works the same way in the classroom – rather than make adjustments as problems arise in the lesson, the teacher anticipates these problems and incorporates modifications into the curriculum from the outset.
That is not to say that one approach is better than the other; in fact, I think it makes sense to include both in the classroom. Teachers should be anticipating student differences and planning for them from the start. However, they should also be monitoring student progress and implementing adjustments that need to be made as they go. I think the two approaches work very well together. The three key UDL principles – providing multiple means of representation, multiple means of action and expression, and multiple means of engagement – can actually be accomplished by altering the process, product, and content of the work, thereby incorporating three key elements of differentiated instruction. Many of the learning centers and differentiated small group activities that seem to be such an important part of differentiated instruction can actually be a great way to provide the range of options for which UDL calls. Therefore, I think the two approaches really complement each other nicely in classroom practice.