What is the relationship between accommodations & accessible instructional materials? How are they the same? How are they different? Is one a subset of the other?

Accommodations are: strategies and tools including AT that allow the student to use the curriculum.
If we look at the National definition of AIM - we understand accessible instructional materials to refer to other ways to access printed text books and other printed core curriculum. Teachers and administrators in our districts have a set defnition of instructional materials so changing the terminology would be hard for a huge barrier in training.

If we understand the State defninition then AIM would be the include accommodations, including accessing printed materials and modifications