We investigated 4 elementary school general education teachers' understandings of the characteristics of students with attention deficit hyperactivity disorder (ADHD) and what academic and behavioral modifications they implemented for these learners. Two major findings emerged: (a) teachers provided few modifications for individuals with ADHD and (b) they provided idiosyncratic, nonsystematic modifications. We followed this investigation with a second multiple case study with 2 middle grade teams in which we examined their understanding of the characteristics of students with ADHD and the modifications they made. The two middle grade teams implemented a variety of modifications that they reported were chosen with the developmental level of their students in mind and knowledge of the resources available, rather than the needs of individual students. We found both elementary and middle grades teachers knew key characteristics of students with ADHD. Although they knew the characteristics and needs of these students, there were few modifications that all or a majority of the teachers made at either grade level.