How Stuff works was initially an online compendium of information articles. How Stuff Works also boast a popular range of podcasts and YouTube channel. Focussing mostly on science, health and technology issues, there is also items on human behaviour and social science-related content too. Aside from a few quizzes, content is mostly text-based, and the target audience is based around KS3/4 students.
Have a look at www.howstuffworks.com