“Visual impairment including blindness is defined in the Individuals with Disabilities Education Improvement Act (IDEA 2004, PL 108–446) as an impairment in vision that, even with correction, adversely affects an individual’s educational performance. The term includes both visual impairments and blindness. Educational services for students with visual impairments are determined by variations of the definition specified in IDEA. This definition encompasses students with a wide range of visual impairments, who may vary significantly in their visual abilities.”