Teachers — We need your feedback! This free, online textbook is an experimental project (see About this Project), and we need to hear from you about whether you believe it is worth our continued time and expense to keep the project going. Please tell us what you think of it, how it works with your students, whether you think it is worth continuing, and if so, what we can do to improve it. You may email any and all feedback directly to lead author Jeff Bennett, jeff@bigkidscience.com. Note: This project is being funded by the lead author. Your purchases of Dr. Bennett’s books on the Big Kid Science site therefore help to support this project.