The 21st annual report to Congress on the implementation of the Individuals with Disabilities Education Act (IDEA) is divided into four sections organized around a model that views educational results as products of three sets of factors: the context and environment in which the education is provided, student characteristics, and school programs and services. Section 1, on context/environmental factors, discusses parent involvement, access to the general education curriculum, and developing a highly trained workforce. Section 2, on student characteristics, focuses on special education in correctional facilities, states' progress in implementing comprehensive early intervention services and special education services for preschool children, and changes in the child count data. Section 3, on school programs and services, addresses paraprofessionals in the education workforce, educational environments for students with disabilities, federal policies on discipline, and the population of students served by visual impairment specialists. Section 4, on student results, discusses graduation requirements and high school completion, state improvement and monitoring, progress on the implementation of transition requirements at the state and local level, and participation of students with disabilities and the use of accommodations in the National Assessment of Educational Progress. Extensive appendices provide data tables. (Individual sections contain references.) (CR)