Students who develop interest in STEM careers by the eighth grade are more likely to pursue careers in STEM (Tai et al., 2006). Interest development can happen through a variety of sources, including informal learning experiences such as out of school programs and summer camps. This study looks at one such informal STEM experience, an engineering summer camp for elementary students, to explore how this camp impacted their understanding, awareness, and attitudes toward engineering. The study used a pre/post design to determine the impact of the camp with two groups of students in two separate years. The results suggest that students gained an awareness of the types of engineering, a better understanding of the purpose of the work of engineers, and had more positive attitudes about the value of engineering and their own aspirations toward engineering.