Take two leeches and call me in the morning. That's probably not what you want to hear from your doctor. Check out some of the most bizarre things humans have done in the name of medicine.

Some are bigger than a school bus. Others are as small as a candy sprinkle. Some make people itch. What are they? Plant leaves! Find out why leaves are a certain shape and size, how they help plants grow, and perform your own experiment to find out just what leaves need to grow.

Italy is one of the world’s oldest countries. Its history is rich with many memorable characters. In this book, readers examine what it is like to live in Italy today. They explore the country’s past and other aspects, such as its economy, government, and food. Complete with colorful photographs, this is a book sure to introduce young readers to an ancient culture.

Warm-blooded animals can control their own body temperatures, while cold-blooded animals are at the mercy of their environment. Young readers can learn how this fact affects an animal’s choice of habitat, take a quiz about what they have learned, and discover species that break the rules. Sidebars zoom in on special traits of both kinds of creatures.

Why do some animals sleep during the day and others sleep at night? The answer is that each species chooses when the best time is to eat and avoid being eaten. Students can explore the characteristics that make a species thrive in daylight or in the dark, take a quiz to test their understanding, and learn about the animals who come out in the twilight hours between day and night.

The puzzling thing about the pufferfish or blowfish is that it is highly toxic yet some people consider it a delicacy. That can make for a dangerous dinner. This book describes how the spikey fish got its name, how it fights off predators, where it lives, the strength of its toxins, and how a skilled chef can render it safe to eat.

When President Thomas Jefferson bought the Louisiana Territory from cash-strapped France in 1803, he doubled the size of the United States without really knowing what he was getting. He dispatched Meriwether Lewis and William Clark and their Corps of Discovery to explore a territory that would include part or all of fifteen future states and to seek a water route to the West Coast. Westward expansion began immediately, all for the bargain price of 15 million dollars. This book richly explores this fascinating part of history.