The purpose of this assessment probe is to elicit students’ ideas about changes that result in new properties. The probe is designed to find out whether students recognize that some things mixed together will retain their properties and others will change. It is best used with students in grades 3–12. Students need to understand they are comparing the properties of the substances before they are mixed together with the properties of the substances after they are mixed together. Encourage students to give examples to support their explanation. The probe is provided in English and Spanish. A materials list, teacher notes, standards, assessment, and references are provided. This book selection also includes the Table of Contents, Preface, Acknowledgments, Dedication, About the Authors, Introduction, and Index.