Clever - syncing between education applications for K-12 schools
OpenToonz - OpenToonz is an animation program that is a free software version of Toonz, the animation software...
PowerSchool - PowerSchool provides a K-12 education technology platform for operations, classroom, student growth, and family engagement.
Synfig Studio - Just another WordPress site
Claroline - Claroline is a collaborative eLearning and eWorking platform.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.