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 Enlarge The Sundae ScoopAuthor: Stuart J. MurphyIllustrator: Cynthia JabarPublisher: HarperTrophyCopyright: 2003ISBN: 0-06-446250-1Number of Pages: 40Ohio Standards Alignment: Grades 2–4Children decide how many different sundaes can be made for the class picnic with a given number of ice cream flavors and a given number of toppings. They explore the possible combinations by charting the choices of ice cream and toppings in a tree diagram.  As toppings spill and ice cream melts, they investigate the effect on the number of original choices. At the end of the story, the author suggests extensions of the activity and lists other ideas, activities, and related literature for teachers.Go to: How to Use This BookHighlights and InsightsRelated ORC ResourcesOhio Standards

 How to Use This Book Introduce the topic of combinations and a simple way of listing them with this story. Adding just one or two other possibilities for ice cream flavors or toppings allows students to see the multiplicative effect of combinations. The author removes possibilities in the story to show the reverse of this effect. Explore the use of the (vertical) chart in this story to compare/contrast the use of a (horizontal) tree diagram to count possible choices. The author suggests other activities such as ordering lunch, making cookies, and getting dressed to show how combinations can apply to other real-life situations that are meaningful for children.
 Highlights and Insights We are faced with the idea of combinations in everyday life -- choice of an outfit, possible pizza toppings, etc. This book is a simple and entertaining introduction to the idea of combinations. I would recommend using a horizontal tree diagram instead of the vertical chart in the story because a horizontal diagram is more natural to read.