Students usually are identified only after consistently demonstrating a failure to understand or follow rules or to complete required tasks.
Other common reasons for referral include frequent classroom disruptions and poor academic performance.
Studies found that students with ADHD, compared to students without ADHD, had persistent academic difficulties that resulted in the following: lower average marks, more failed grades, more expulsions, increased dropout rates, and a lower rate of college undergraduate completion (Weiss & Hechtman as cited in Johnston, 2002; Ingersoll, 1988).