The University of Miami, as part of a larger study, will develop a direct assessment of preschool science which can be used to measure science content and process skills among preschoolers. The assessment will evaluate interventions in classrooms serving Head Start children. Specifically, the goal of this study is to study the gender differences in answer choices on assessment items. The study has two objectives: (a) to address whether items are measuring science skills differently for either male or female children; and (b) to qualitatively evaluate items to address possible reasons for gender differences in answer selection. Expected results of the study will provide a measure of preschool science that is fair to both boys and girls for use in future studies. The project will help disseminate information on a relatively accessible method for detecting item bias that other researchers can use in their validation of measures created for Head Start, or other preschool settings.