The Nature of Light Interactive E-book* explains the characteristics of light, discusses the concept of light as waves, explores the idea of light and color, and ultimately answers the question, "What is light?" Topics covered include reflection and refraction, the electromagnetic spectrum, light perception, and emission spectra and absorption spectra. Teachers, students, and lovers of science will find the clear and concise format engaging and informative.

The Heredity and Variation Interactive E-book* explores patterns of inheritance and discusses how offspring can look similar to their parents yet still possess differences within their genetic code. These differences can sometimes affect (positively or negatively) an offspring’s ability to survive and reproduce. This e-book focuses on historical evidence for inheritance, probability and graphic representations of inheritance, the DNA molecule, the influence of genes on our traits, the process of meiosis, and mutations.