Heating or cooling different materials may cause them to change. Heating some materials might cause them to melt or cook. Cooling some materials might cause them to change color or form. Some of these changes are reversible, while others are irreversible. This nonfiction Beginning-to-Read book contains high-frequency words and content vocabulary. Connecting Concepts pages include a word list along with activities to strengthen early science and literacy skills, such as understanding nonfiction text, science in the real world, science and academic language, fluency, and finding further information. Aligns with Next Generation Science Standards for Grades K-3.