How Stuff Works
If you want to know how ANYTHING works, I'm sure you can find it here!  This is a WAY COOL site!

MadSci Network
LOTS of questions and answers, about every part of science you can imagine.

Ask an Expert
Questions about all sorts of science, especially for students and teachers.

Ask a High Energy Astronomer
Astronomy questions answered by real NASA astronomers.

Ask the Space Scientist
Another astronomy site brought to you by NASA.

Ask a Physicist
Yet more questions answered by NASA astrophysicists - this time on all different parts of physics.

Ask an Earth-Scientist
Answers to geology questions, courtesy of the University of Hawaii.

Science Whatzit!
Science answers from the Oregon Museum of Science and Industry.

There's a lot more Q&A sites out there, but if you've got one that you'd like to see on our site, we'd like to know.  So please, tell us.  Thanks!