These titles introduce the basics of measurement to very young readers. Easily understandable text explores time, temperature, and other quantifiable characteristics. Photos show various children using tools for tasks, such as a tape measure to find the length of a board and a stopwatch at the races. There are also comparisons between the imperial system and the metric system. Other pages explain how smaller units can combine into larger ones or how different types of tools are used for larger or smaller measurements, such as a ruler versus a yardstick. Each book offers suggestions to adults for before, during, and after reading, as well as a photo glossary combining the terms in bold from the text with thumbnail images from the illustrations. Back matter also includes a sight word list. VERDICT Clear images support simple explanations, making this a good series for primary grade math and science classes.