Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Teachable - Create and sell beautiful online courses with the platform used by the best online entrepreneurs to sell $100m+ to over 4 million students worldwide.
TaskPaper - Plain text to-do lists for Mac
Clever - syncing between education applications for K-12 schools
Microsoft To-Do - Task management tool
Claroline - Claroline is a collaborative eLearning and eWorking platform.