The purpose of this assessment probe is to elicit students’ ideas about forces. It is designed to find out whether students recognize that balanced forces act on a stationary object. It is most appropriate for middle and high school students. Elementary school instruction is primarily focused on describing the position and motion of objects and discovering the various kinds of forces that affect the motion of objects. Middle school students engage in concrete experiences from which a more comprehensive understanding of force will develop. High school students can begin to understand the qualities of the electromagnetic forces that are dominant among atoms and their smaller particles. Teacher notes, standards, assessment, and references are provided. This book selection also includes the Table of Contents, Dedication, Preface, Introduction, and Index.