This book includes 50 situations that present interesting opportunities and challenges to stimulate students' creative and critical thinking. The brief, practical, everyday situations provide motivating starting points for practicing Creative Problem Solving with groups of many ages. These problems were designed to represent a variety of different tasks or challenges in an open-ended, invitational format that we describe informally as a "Messy Situation." These Messy Situations, like many of life's everyday opportunities and challenges, take a variety of forms, sizes, and shapes. They might concern a variety of situations in which people find themselves day in and day out. Thus, some of the Messy Situations in this book are people tasks (that is, situations involving the interactions or relationships among people). Others are planning tasks (that is, concerning more effective ways of organizing or managing a situation), and yet others are product tasks (that is, challenges that call for designing, inventing, or producing a new product of some kind). Each of these one-page problems can help students learn and apply CPS components, stages, and tools in an engaging and enjoyable way. Choose the problems that are best suited to your group's interests and needs. The challenges in Practice Problems for Creative Problem Solving and several helpful worksheets are reproducible for classroom use.