Did you know that the first time you come in contact with poison ivy, you probably won't get a rash? Every time after that, though, is a different story. Learn how to spot different varieties.

Entire or toothed? Being able to distinguish between these two types of leaf margins will help you identify a plant specimen. This illustrated guide shows you what both look like.

At a loss for words when it comes to explaining your biodiversity findings in the classroom, field, or lab? Increase your vocabulary—and observation skills—with this guide to gathering clues.

Don't just take a close look at that arthropod, pick up a pencil and draw it! You'll be surprised how much better you'll understand and appreciate what you're seeing.

See how a day of collecting rocks on the north shore of Long Island turned into an exploration of the Earth's history for this eighth-grader from New York.

The meandering stream that carved West Virginia's natural land bridge also helped create diverse layers of rock at its foundation. Tour the area's geological past with this ninth-grader.

Fiddler crabs never stray far from their burrow. That's why they will do anything to avoid getting caught and measured, as this ninth-grader from Virginia found out.

The work of Gregor Mendel—today known as the "Father of Genetics"—was disregarded by his fellow scientists. Learn how it was rediscovered decades later in this winning essay by a California teen.

Wolves have long been the favorite animal of this eighth-grader from Illinois. Learn how she turned her interest into an insightful experiment about how wolves calm and comfort each other.

It can seem that the desert ecosystem is devoid of much life. But this Arizona teen found biodiversity just by turning over a few ironwood tree trunks she found in the sand.