The driving question for this brief is based on the most common question that teachers, principals, school leaders, coaches, and grant writers ask the Buck Institute for Education (BIE) about Project Based Learning (PBL): What evidence exists that shows the impact of Project Based Learning on student learning in core content areas? Research shows that PBL "can" promote student learning and may be more effective than traditional instruction in social studies, science, mathematics, and literacy. The 20 studies reviewed in this brief show that PBL can promote student learning in social studies and science; and, to a more limited degree, in mathematics and literacy. As research continues to build, practitioners who are interested in using PBL can point to the studies in this brief as evidence of the promise of PBL in improving student outcomes. The "Digging Deeper" section is designed to provide practitioners with a high-level overview of these studies.