Will it kill you or cure you? Test your knowledge with this quiz.
See how good you're at recognizing emotions.
How fast can you catch a falling ruler? Measure your reaction time.
Take the jellybean test to see how your sense of smell enhances taste.
Use Braille to create a message for a friend.
Explore your nerves by creating a life-sized drawing.
Try these trippy experiments to fool your brain.
Scientist Rob DeSalle answers kids' questions about the brain!
Test your sight and memory with these brain games.
Photos: Ed Mathez headshot, © AMNH/D. Finnin. Satellite image of United States, Earth globe, ice, coral reef, © NASA. Smog, © US EPA. Polar bears, © US Fish & Wildlife. Flooded house, storm, cracked land, © USGS. Crowd, © Flickr.com/kaim_a. Wind power, © Glowimages/AGE Fotostock. Lightbulb, © A. Booker. Electronics, © iStock. Bikes, © M. Tarr.
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