IXL- Sign in to practice math at home or at school.
That Quiz- A fantastic site for practicing basic facts and other math concepts. Students can select the length and difficulty of the "quiz". Students are also given chances to correct their mistakes at the end of the quiz.
Family Math Challenges- FigureThis! is a great site for families that want to explore cool math investigations together. The activities are great for practicing thinking skills and offer students a chance to be creative problem solvers. The activities are meant to be printed and can be completed without the use of the computer.