The Earth: Its Structure & Its Changes is the latest in the Investigate the Possibilities elementary science series by Master Books. For each of the investigations in this paperback book, the suggested learning progression is to Engage, Investigate, Explain, Apply, Expand, and Assess. Although this sounds like a mouthful and may seem daunting, the chapters flow naturally through the process, and even the non-scientific teacher will find the text easy to use and understand. The students will learn about maps, mountains, earthquakes, crystals, minerals, caves, glaciers, and more. The investigations include such things as making sinkholes, volcanoes, rock layers, and fizzing rocks. All of the experiments in the book use commonly found objects and ingredients.

The "Introduction" and "How to Use This Book" sections are well written, and the colorful photos help create enthusiasm about earth science for the teacher and students alike. The authors are unapologetically Christian and offer websites for additional proof of their beliefs. Each chapter starts with an engaging "Think About This" section. Next, the "Procedure and Observation" section leads the students through the investigation or experiment with clear directions. "The Science Stuff" explanation follows; then the "Making Connections" section shows the students how to apply what they've learned. They are then asked to "Dig Deeper" (or expand their understanding of the subject). And finally, the "What Did You Learn" section assesses their comprehension of the chapter.

Easily taught to children of various ages simultaneously, The Earth: Its Structure & Its Changes is primarily aimed at students in grades 3-6. It has 20 chapters and thus could be used once a week for a yearlong course, a co-op class, or a nature club. Or you could complete a few chapters per week to use it as a one-semester class.

A separate Teacher's Guide & Student Journal is available for this course. At only $6.99, it is an affordable supplement that includes hints for teaching, and the student section has pages for recording observations, ideas, questions, and answers from the text. The student pages are perforated and can be copied for multiple students.

Pros: There are many reasons to use this curriculum. For me, the best ones include the multi-age capability (I have 8- and 10-year old boys), easy-to-find objects used in experiments, the flexibility of using it once a week or as a daily science class, and the fact that the authors are Christian. Another incentive is the reasonable price of $12.99.

Cons: Although I could use this book alone to teach elementary earth science, I would prefer to have the teacher book and student journal included as well.

When I was in school, I loved earth science class. The teacher, the field trips, and the projects made all the difference. My husband, who went on to become a secondary science teacher, did not enjoy earth science at all when he was in school and still turns his nose up at it. I am confident that this book will help my kids (and perhaps even my hubby) enjoy the earth science experience as much as I did!