As part of a larger study, the How My Library Supports Inquiry and the How My Science Class Supports Inquiry questionnaires were developed for evaluating the extent of inquiry-based teaching in classrooms and school libraries and the effect of this instruction on student literacy and, by extension, the social good. Each has 28 items in seven scales measuring students' perceptions of the degree to which certain psychosocial factors are prevalent in the science class and the school library. Using data from 872 elementary students and 639 secondary students, principal components factor analysis with varimax rotation and Kaiser normalization confirmed the a priori structure of the questionnaires. The factor structure, internal consistency reliability, discriminant validity, and the ability to distinguish between different classes and groups were supported for both instruments. Validation of these instruments enables consideration of a new approach for assessing the contribution of school libraries to the field of education, with specific emphasis on science education through the study. In addition, this study makes a unique contribution to the field of learning environments by evaluating the relationship between school library programs and classroom environments.