Grockit is an online social learning community--good for test preparation for SAT, ACT, GRE etc. Of course, they are trying to get you to purchase theiri online test preparation program. Might be helpful to persons working with secondary learners.
Put away your EZ-graders, teachers, QuickGrade is the easiest grade calculator around! Use this tool to make grading stacks of tests a snap. Made with love and totally free to use!