Solids, Liquids, Gases, and Plasma

Gr 2-4–Adler makes a commendable effort to introduce younger readers to a complex topic, with mixed results. He combines simply phrased explanations and demonstrations using measuring cups, balloons, and other common materials to make the differences between each classical state of matter easy to comprehend. The author goes a step beyond most similar overviews, notably Kathleen Weidner Zoehfeld’s What Is the World Made Of?, by tackling plasma as well. However, he doesn’t acknowledge the possibility of other states of matter (the University of Cambridge and the Oak Ridge National Laboratory discovered a new state of matter in 2016, as published in Nature Materials) and, more significantly, simplistically identifies smoke as a gas. Raff’s bright cartoon illustrations add clarifying details and humor. Throughout the narrative, a frazzled dad messily undertakes the described demonstrations…helped by a dog who produces gas of its own.