This is a tutorial and video series from WAI/W3C. Using this website and its content organized in 6 tabs across the top of page could be an excellent and thorough introductory tutorial. It contains many links to other resources too. Their Perspectives Videos are well-done and informative.
From U of MN: “Eliminating barriers for an individual upon request (accommodation) is good and important. Better is creating an inclusive environment that naturally welcomes all gifts and allows them to be given (accessibility).” Their page explaining the Impact of accessibility in Digital Environments is a nice summary of key issues.
Useful infographic providing an overview accessibility in education.
Introduction to Section 508 and Information and Communication Technology (ICT). Explains what Section 508 is and why it’s important, how Section 508 conformance can make ICT more accessible, reviews job-related responsibilities for meeting Section 508 standards, offers resources to help you meet your Section 508 responsibilities.
High-level overview of the Revised 508 Standards. Explains roles and responsibilities of Federal government executives, including agency heads, CIOs and CAOs, and Section 508 Program Managers.
By Penn State with links to WebAIM and W3C