"SEN Teacher provides cost-free teaching & learning resources for students with special needs and learning disabilities." That's how this repository of special education resources sums itself up. (SEN is the acronym from the UK that stands for Special Education Needs.)
SEN Teacher offers a substantial collection of "printable" (and brailleable) downloads. There are links to websites that provide information about a wide range of disabilities, free online resources, and freeware download sites. The free software listed here includes programs to help develop basic mouse and other computer
skills that may assist someone with low vision, programs to practice switch use, programs that support curriculum, and much more. There are even a few programs by SEN Teacher itself (1-5 Counting, 3D Shape Venn, Buried 3D Shape, Girl Face Matching). I think you'll find something of use here.
Click this link to visit http://www.senteacher.org.