Maths Interactive Games Primary
I'm a big fan of online games and simulations that allow children to virtually experience and experiment with concepts that may otherwise be difficult to test out, or in preparation for a physical experiment. That's why I'm highly recommending the University of Colorado's free online PhET project: Interactive Science Simulations.
The PhET project provides free online physics, chemistry, biology, earth science, and math simulations that are fun, interactive, and research-based. Educators can browse the activities section by simulation type and grade level. PhET offers special workshops and materials for educators.
Science Simulations
In Science Activities Online, Amy Martin says that educators who teach science online don't have to give up doing traditional hands-on experiments, because science simulations can replicate classroom labs. Martin recommends several sources for online simulations: