A study determined the impact of integrating literacy and science programs on literacy achievement, use of literature, and attitude toward reading and science. Six third-grade classes (128 students) of ethnically diverse children were assigned to one control and two experimental groups (literature/science program and literature only program). Standardized and informal written and oral tests were used to determine growth in literacy and science. Use of generic literature and literature related to science was measured by a child survey concerning after-school activities and records of books read in school and at home. Interviews with teachers and children determined attitudes toward the literature and science programs. Children in the literature/science group did significantly better on all literacy measures than children in the literature only group. Children in the literature only group did significantly better on all literacy measures, except for the standardized reading tests, than children in the control group. There were no differences among the groups on number of science facts used in science stories written. In the test of science concepts the literature/science group did significantly better than the literature only group and the control group. Observational data are reported on the nature of literacy and science activity during periods of independent reading and writing. (Contains 42 references, 4 tables, and 4 figures of data. A list of storybooks used for testing is attached.) (Author/RS)