iSpring Free - iSpring Free is a free eLearning authoring tool that allows you to create responsive courses and quizzes right in PowerPoint and convert them to HTML5 or SCORM.
Synfig Studio - Just another WordPress site
Open Elearning - Free and open source software for editing courses and educational games easily.
OpenToonz - OpenToonz is an animation program that is a free software version of Toonz, the animation software...
Slidego - At SlideGo we regard presentation software like Powerpoint as a universal authoring tool.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.