Robert Gardner & Phyllis J. Perry 
Ace Your Plant Science Project [PDF ebook] 
Great Science Fair Ideas

How do different types of soil affect germination? How do light and dark affect leaves? Can you tell how old a tree is? Young scientists will explore structures, development, and life cycles of plants and interactions of plants with their environment? Readers will learn the answers to these questions and more with the fun life science experiments in this book. Following the scientific method, readers will be able to use many of the science fair project ideas for their own science fair project.