An introduction to time discusses the inventions and communication used to tell time throughout history, including hour glasses and atomic clocks to calendars and chronometers.

Explains how to use clocks and watches to tell the time; describes the different increments of time, from seconds to years; and discusses how speed is related to time.

Learn about clocks and calendars and how they measure time.

"The joy of the changing seasons means saying hello to new but familiar rituals, like spring picnics in the park or homemade lemonade in summer. But there's also the bittersweet feeling of doing something for the last time, like mowing the lawn one final time on a brown day in autumn or watching the last of the geese fly south"--

America's most celebrated astrophysicist invites young readers to explore the mysteries of the universe.

Explore real world examples to learn basic mathematical concepts in this title.

"In human experience, time travel has always been the subject of fantasy stories. But as scientists learn more about people and the universe, they're starting to realize that some forms of time travel might be possible"--

This book describes what the clock measures and why knowing how to tell time in seconds, minutes, and hours is important, and it discusses the history of time measurement.

"The idea of time travel is one that never gets old. It has enthralled the imaginative, the serious, and the scientific for centuries. Your readers will learn the science behind the fantasy of time travel, the theories behind such an ability, and the inventions that are trying to get us to the past, and beyond"--Provided by the publisher.

"Adorable photographs of puppies and kittens guide elementary students though the basics of telling time. Starting with 'Words to Know, ' which introduces students to new vocabulary before encountering it in the text, this volume proceeds to explain how to read time from analog and digital clocks to the half hour, the difference between a.m. and p.m., and the various ways to write the time. Fact boxes and activities enhance the math concepts. A further...