The Case of the Shrunken Allowance (Hello Reader! Math, Level 4)

This book is designed to teach the basics of money changing to children in grades 2 and 3. P. B. is a boy who likes peanut butter sandwiches and he also puts his allowance in empty jars to store it up. However, he recently noticed that the level of coins in the jar has dropped so he thinks someone is stealing it. The jar is on the window sill and he has it staked out. His friends Maria and Mike are walking by when they spot him and ask him what he is doing. Shortly after they all eat a sandwich, they see P. B.'s sister Jill take money out of the jar. When she comes out, they confront her and she says that while she took coins out of the jar, she replaced them with dollar bills, which take up less space. Jill also tells them that yesterday the cat knocked the jar down and it broke. She replaced it will a larger jar, which explains why the level has dropped. They all go out to the garage where they count the money and it turns out that it is all there. This story is meant to be the prelude for a series of exercises to give to the students about counting money and the different ways in which a certain amount can be expressed. It will interest the students and lay the proper foundation for the activities which appear in the back of the book. The combination of story and exercises is very well done.

Teacher could use this to create a cross curriculum lesson using problem solving, deductive reasoning, and perceptions vs. truth. There are some great lessons to be learned from this story and Math is one of them. Children can be introduced to money values, counting, and estimating of time and container sizes. Plus they can learn to use various coins to make the same amount. I enjoyed reading this to my family and seeing their reaction and problem solving skills at work. The author also provides several lessons you could use in the class. Great book for 2nd and 3rd graders to enjoy.