Although learning science in informal non-school environments has shown great promise in terms of increasing interest and engagement, few studies have systematically investigated and produced evidence of improved conceptual knowledge and cognitive skills. Furthermore, little is known about how digital technologies that are increasingly being used in these informal environments can enhance learning. Through a quasi-experimental design, this study compared four conditions for learning science in a science museum using augmented reality and knowledge-building scaffolds known to be successful in formal classrooms. Results indicated that students demonstrated greater cognitive gains when scaffolds were used. Through the use of digital augmentations, the study also provided information about how such technologies impact learning in informal environments.