The use of games to introduce elementary school children to some concepts about environmental factors is described in this group of five documents. Teaching procedures to investigate wind, shadows, liquids, colors, and color change, and aspects of sampling populations are outlined. Simple apparatus and experiments are suggested, and details of the construction and preparation of the materials are given. The following ideas are developed: the nature of different types of water pollutants depends upon physical properties of liquids; color change can be an index of other changes in organisms; shadows are predictable and related to movements of earth and sun; shade has effects on organisms; environmental factors have an effect on wind speed and direction; and factors influencing the validity of statistical samples are sample size, sample selection, and sample number. Opportunities for interdisciplinary activities are mentioned, particularly those using mathematical skills. Background information for the teacher is included in all units. This work was prepared under an ESEA Title III contract. (AL)