Roll20 - Roll20 is a suite of easy-to-use digital tools that expand pen-and-paper gameplay.
Clever - syncing between education applications for K-12 schools
GOG.com - DRM-free game store, selling both new and old titles. No clients required.
PowerSchool - PowerSchool provides a K-12 education technology platform for operations, classroom, student growth, and family engagement.
Diep.io - Diep.io is a multiplayer action game available for web browsers, Android, and iOS, created by Brazilian developer Matheus Valadares. Players control tanks and earn points by destroying shapes and killing other players in a 2D arena.
Claroline - Claroline is a collaborative eLearning and eWorking platform.