Free & Open-Source Khan Academy Kids Plus Alternatives

Premium tier of Khan Academy Kids.

1. Khan Academy ↗
   Free world-class education on the web.
   ●○○Easy · Strong feature parity
2. CK-12 ↗
   ●○○Easy · Strong feature parity
3. MIT OpenCourseWare ↗
   All MIT class materials, free.
   ●○○Easy · Strong feature parity