Every four years something funny happens with our calendars -- we add a day! Why do we do this? Discover the science behind leap year.

Be a glow-getter with this energy transfer worksheet!

Learn about pearls, which seem like normal jewelry from a factory but are actually made from the mucus of mollusks!

Where to flower babies come from? Use this word search to learn about the different pollinators in our environment, and how they help spread plant seeds.

Where do flower babies come from? Find the answers in this word search about plant reproduction!

Get familiar with this food chain pyramid, from carnivores and herbivores to producers and decomposers; each group has a role.

Fourth and fifth graders will cut out and assemble a human skeleton from paper in this engaging life sciences printable.

Go from a butterfly beginner to an expert with this worksheet, full of pretty butterflies and tons of information about where butterflies live.l

Are students studying electricity? Give them a break from the scientific nitty-gritty with this fun word search full of electricity terms!

There are many animals around the world whose lives or homes are threatened. Read about an endangered species from Africa with this info-sheet

Did you know cougars can leap 20 feet from a sitting position? This fun worksheet is jam-packed with fun facts about the cougar!

Where'd that shadow come from? Next time a scary shadow crosses your path, you'll know just what to look for.

Let your kid's knowledge of leaf vocabulary climb as high as a tall, tall tree with this fun word search.

Discover how water flows in this informative environmental science worksheet!

Get to know some of the friendly, furry, feathery river wildlife that live near American rivers, then match each one to its home.

Step up to the controls, Dr. Frankenstein -- the world is in need of a new creature!

Let your child explore the vocabulary associated with Earth's landforms with this colorful word search.

Roses are red, violets are blue, I know the parts of a flower, how about you? Learn about flower anatomy with this worksheet.

Test your knowledge of electrical energy with this third- and fourth-grade worksheet!

Explore magnetism with this colorful science worksheet for third and fourth graders!

Dig into the details of plant growth with this worksheet for fourth and fifth graders!

Learn all about rivers--how they were formed, what they're made of, and what they do for us and the planet--in this reading and science worksheet.

Learn about the farthest planet in our solar system, Neptune. Facts include interesting bits about the vast winds that keep its surface moving!

Looking for a worksheet to help your kid with science? This printable will help him with his knowledge of geology.

What is the water cycle? We're glad you asked! Learn about this amazing natural system that's been working for billions of years.

Dive deep into your body's circulatory system with this worksheet on blood and what it's made of.

Review energy terminology with this fun fourth-grade crossword puzzle!

Introduce children to physicist Albert Einstein — and a bit of theoretical physics — with this mini biography.

This multi-page worksheet provides an opportunity for kids to practice both their understanding of food webs and their reading comprension skills.

Peel back the layers of the earth in this earth science worksheet. Can you name all of them?