Böcker av Ava Sawyer

Nitrogen, oxygen, argon and carbon dioxide are all gases in Earth's atmosphere. But what happens when there is too much or two little of a certain gas? Readers will learn how everyday activities such as driving, heating buildings and using aerosols release harmful gases into the air and how it affects the air we breathe.

Sedimentary rocks are all around you. They form from soil, gravel, dust and other sediment. This type of rock is often affected by wind and water erosion. Learn how this can change an area's landscape and how sedimentary rocks are useful.

Did you know rocks could go through metamorphosis? Intense heat or pressure changes the form of metamorphic rocks. This type of rock is the oldest found on Earth. Find out where metamorphic rocks are formed, how they've impacted the planet's landscape and more.

Did you know igneous rock is formed as a result of volcanic activity? This type of rock is made up of minerals. Find out more about minerals, where igneous rocks form and what purposes they serve. You may even have igneous rocks in your own home!

How do we know about the plants and animals that lived millions of years ago? Fossils! Every continent contains fossils that tell us about organisms that once existed on Earth. Fossils also give us details about what the planet was like in these prehistoric times. Find out how fossils are formed, how they are identified and much more.

The hydrosphere encompasses all water on Earth from glaciers and ice to rivers and oceans. People use water every day. This title asks the question, how much do you use? Readers will learn how humans use water, how humans positively and negatively affect water and how to protect the water supply.