ENVIRONMENTAL EXPERIMENTS ABOUT LIFE

In the ``Science Experiments for Young People'' series, some disappointing experiments on ecosystems, life cycles, pollution, and conservation. Though simple household materials are employed and the authors give plentiful warnings, procedures, observations, and things to try, few of the experiments follow scientific method. Some are merely observations (``What kinds of animals can you find under a log or rock?'') or definitions (``What is Indoor Pollution?''). Multiple variables are not always adequately controlled, and some conclusions are puzzling. In ``Do Plants Use Carbon Dioxide?'' the authors use three samples to test five variables: more samples and controls are needed, and the experiment doesn't prove either that the resulting gas is oxygen or that the gas is a result of photosynthesis. A hot topic, but poorly explored. Index. (Nonfiction. 10-12)