Perhaps you’re an avid birder, or maybe you want to do something about noxious weeds. You might have a telescope, and you spend your nights looking at the sky. Or maybe you drove your parents crazy (as I did) bringing home bugs and rocks and frogs and snakes—and you still haven’t outgrown your fascination. Having a hobby is fun, but turning it into something more significant is even better. No matter what your interest, you can put your knowledge and skills to good use as a citizen scientist.