Science is considered a critical area within the curriculum and instruction by teachers alone is not enough to ensure success for all students. School librarians must be considered in delivering science information to students, particularly those who are second language learners. This two-year study examined the effect of teacher and librarian collaboration (TLC) on inquiry-based science information literacy of Latino students in the United States. Although no significant gains were found between Control and Intervention classes, qualitative data indicated that TLC was successful in motivating students, improving inquiry and information literacy, and understanding of science concepts. The implication is that that test scores alone do not provide a complete assessment of student learning. Factors limiting student gains included reduced science and library time, and state policies that removed second language learners from regular classroom instruction. Continued advocacy for TLC is recommended to provide students needed tools for long-term academic success.