The development and validation of a test of science problem solving skills for use in grades one through three are described. Norms (grade placement scores) for children in urban, outer-urban, and suburban areas are provided for the total score on alternate forms of the test, each of which uses two physical science problems to assess (1) the ability to recognize the problem, (2) understanding of the science principle needed to solve the problem, (3) the ability to collect data, and (4) the ability to use "if-then" reasoning. The test has a K-R 20 reliability of 0.82. Test scores can be used to identify patterns of strengths and weaknesses in problem solving skills of individual children. Total mean scores increased with grade level, and suburban children performed best at all grade levels. Outer-suburban students obtained higher mean scores than urban children, except in grade one, where there was no significant difference. (Author/AL)