BookWidgets - BookWidgets is an excellent application that let you create engaging exercises in minutes and easily share a varied variety of beautiful and fun activities with your classroom and others.
Terraria - Dig, Fight, Build! The very world is at your fingertips as you fight for survival, fortune, and glory.
Padlet - Visual boards for organizing anything.
SimPhy - Interactive 2D & 3D Physics simulation software
Quizlet - Quizlet allows you to review and create flashcards for a variety of subjects, such as math and reading.
Physion - Physics Simulation Sandbox