Computer science is all around us, at school, at home, and in the community. This book gives readers the essential tools they need to understand the computer science concept of testing. Brilliant color photographs and accessible text will engage readers and allow them to connect deeply with the concept. The computer science topic is paired with an age-appropriate curricular topic to deepen readers' learning experience and show how testing works in the real world. In this book, readers learn why it is important for chemists to check their work. This nonfiction book is paired with the fiction book Kara Is a Chemist (ISBN: 9781508137580). The instructional guide on the inside front and back covers provides: Vocabulary, Background knowledge, Text-dependent questions, Whole class activities, and Independent activities.