As usual, Branley has presented science in a clear and very readable format. However, Day Light, Night Light has a limited content scope--natural and man-made sources of light and seeing objects from reflected light. Other books in this "Let's read and find out science" series have a much broader usability because of the excellent content which stretches their appropriateness higher than the reading level of the text. I often look for books by Branley and others in this series for my curriculum development work.