When making software procurement decisions, educational entities need to look critically at which products in a given software category will best serve the needs of all students, without excluding some on the basis of disability. To determine whether a software application is accessible, the application should be evaluated according to a set of guidelines or standards that defines software accessibility.
The only legal standard is Section 1194.21 ("Software applications and operating systems") of Electronic and Information Technology Accessibility Standards. These standards were developed by the Access Board as required by Section 508 of the Rehabilitation Act Amendments of 1998. There are twelve standards, and the Access Board provides a detailed explanation of each in its Guide to the Standards.
Additional guidelines and resources are provided in the Knowledge Base article How can I tell whether a software application is accessible?