Field trips are an important feature of the United States' education system, although in the current context of high-stakes tests and school accountability, many schools are shifting resources away from enrichment. It is critical to understand how field trips and other informal learning experiences contribute to student test scores, but little research has explored the impact of field trips on standard measures of academic learning. In this study, I used 6 years of student-level data to estimate the impact of field trips to informal science education institutions on New York City students' performance on the state's standardized eighth-grade science exam. Using a rigorous identification strategy with school fixed effects to capitalize on variation in field trip participation within schools over time, I found small positive effects of exposure to field trips on students' science test scores and proficiency. Effects were largest for Hispanic students and those who qualified for free or reduced-price lunch. This evidence that field trips can contribute positively to student achievement is meaningful for policymakers and administrators, as it suggests schools can provide enrichment experiences that families desire without sacrificing student test scores. The study suggests that field trips might be an effective tool for reducing achievement gaps.