Students with disabilities often face barriers that hinder their capacity to access general education curricula and show their learning. Modifications to curricula and lesson plans can help reduce these barriers. Modifications are changes to what instruction is delivered--which tasks students complete and what content they learn. Previous research indicates that general educators often have less training and confidence in their abilities to appropriately modify instruction for students with disabilities than special educators do. However, little is known about how and the extent to which general and special educators modify their lessons to make them more appropriate for day-to-day use with students with disabilities. In this Data Note, researchers explore teachers' reports of how much and in what ways they modify their lessons to support students with disabilities. The examination uses data drawn from the American Instructional Resources Survey, which was fielded in May and June 2020 to a nationally representative sample of general and special education teachers who are part of the RAND Corporation's American Educator Panels. [For a related report, "American Instructional Resources Surveys: 2020 Technical Documentation and Survey Results. Research Report. RR-A134-4," see ED611144.]