Aurora Gil has created this interactive website thinking in her students. Hope she doesn't mind to share it with us
Easy, intermediate and advance grammar exercises and games. It also has some very interesting issues to think and work with them, themes like : Child labour, anorexia and bulimia, domestic violence, global warming, clitoridectomy and immigration.
If you understand Spanish there are also guides for students and teachers, anyway you can go directly to the menu page and start working. Enjoy it!