A good science book for the junior high school level, but weakened by haphazard organization and dull illustrations by Ruth Black. The authors, science editors of Young America, have enhanced the interest and value of each experiment by relating it to the reader's experience, rather than just tossing a lot of how-to-do-it activities at him. Simple materials, fairly clear directions and vivid results show careful planning within each experiment, but the book as a whole is lacking just such careful planning. There is absolutely no discernible relation between one experiment and the next, and no attempt to capitalize on previously learned facts in the introduction of new material. A little shuffling around could have resulted in several groups of experiments, each with a central theme, such as light, heat, chemicals, etc. Thus, the principles of optics learned through building a range-finder might have been clinched by following up with the construction of a periscope, which instead is placed many pages away. Nor will the clear, but uninspired illustrations invite the non-science minded. A little editorial work could have improved the book considerably.