“Twice exceptional” (2e) is the term used to describe intellectually gifted children with great potential for academic achievement who also have a learning disability or neurological challenge, like attention deficit hyperactivity disorder (ADHD or ADD), autism, etc. Their exceptional intellectual abilities of 2e students are often masked or obscured by one or several conditions (or vice versa).
Links to the federal guidance:
Office of Civil Rights – Dear Colleague Letter: Access by Students with Disabilities to Accelerated Programs December 26, 2007: https://www2.ed.gov/about/offices/list/ocr/letters/colleague-20071226.html
Office of Special Education Programs – Letter to Anonymous, January 13, 2010: https://sites.ed.gov/idea/files/idea/policy/speced/guid/idea/letters/2010-1/redacteda011310eval1q2010.pdf
Letter to Delisle in December 20, 2013:
Letter to Delisle: https://sites.ed.gov/idea/idea-files/policy-letter-december-20-2013-to-dr-jim-delisle/
Special Education Field Advisory Memo from June 2015