Ubermix

http://www.ubermix.org/ The ubermix is an all-free, specially built, Linux-based operating system designed from the ground up with the needs of education in mind. Built by educators with an eye towards student and teacher empowerment, ubermix takes all the complexity out of student devices by making them as reliable and easy-to-use as a cell phone, without sacrificing the power and capabilities of a full operating system. With a turn-key, 5 minute installation, 20 second quick recovery mechan...
More

Edubuntu

http://www.edubuntu.org/ Edubuntu is a grassroots movement, we aim to get Ubuntu into schools, homes and communities and make it easy for users to install and maintain their systems.  We are students, teachers, parents and hackers who believe that learning and knowledge should be available to everyone who wants to improve themselves and the world around them.  Our aim is to put together a system that contains all the best free software available in education and make it easy to install and ma...
More

Sugar

https://www.sugarlabs.org/ Sugar is a learning platform that reinvents how computers are used for education. Collaboration, reflection, and discovery are integrated directly into the user interface. Sugar promotes "studio thinking" and "reflective practice". Through Sugar's clarity of design, children and teachers have the opportunity to use computers on their own terms. https://www.sugarlabs.org/
More