Grade 3

For over 20 years, Undertaker has been an almost unstoppable force in WWE. He has collected a record 21 WrestleMania wins, and that's just one accomplishment! When Undertaker eventually makes More →

Much of our understanding of ancient plants and animals comes from the fossil record. Big or small, fossils offer images of life on Earth from billions of years ago! Young paleontologists… More →

When it comes to lemurs, it's a woman's world. Females rule—they eat first, win all family arguments, and fight enemies on the front lines. Learn why you'd want to be “one of the ladies” in a More →

Underwater, a large, lively community of unique animals thrives. Many of these animals belong to the fish class. There are colorful clownfish, lurking sharks, and silly sea horses. There are… More →

Iceland is known as “the land of fire and ice.” This is because the island has around 200 volcanoes and about a tenth of its area is covered with glaciers. The colors of the national flag… More →

As a country of 17,000 islands, Indonesia is truly unique. It's fitting that many rare animals make their homes in Indonesia. The venomous Komodo dragon, one of the deadliest animals in the… More →

Members of the insect class often get a bad rap. People swat at them, stomp on them, and go to great lengths to repel them. Though some insects are pests that spread disease, many are… More →

The largest animal alive is a mammal. It's the 150-ton blue whale. This whale is not only large but also loud—louder than a jet engine! Turn the pages of this book to learn about the… More →

Dinosaurs, the world's most notorious reptiles, became extinct a long time ago. However, their cold-blooded, scaly reptile relatives still creep around today. While people no longer have to… More →

Trespassing in mountain lion habitat is a dangerous idea. Mountain lions do not share their territory, and they will not hesitate to stalk, pounce, and bite to defend it. Read about people… More →

Some animals lead a double life. First, they pose as aquatic creatures, breathing through gills and using tails to maneuver underwater. Then they exchange these features for legs and lungs to More →

Compare a hummingbird and an ostrich; the differences are striking! One is tiny and hovers in the air like a helicopter. The other is massive and stays grounded, sprinting rather than flying. More →