The goal of most science festivals is to increase the science literacy of the slice of the American public they serve. The number of science festivals around the country has grown exponentially over the past 10 years. They have quickly come to be regarded as entertaining, experiential ways to present scientific information to general, community-based audiences. But how effective are they? We wondered, and so we developed EvalFest, a $1.8 million research project funded by the National Science Foundation; Morehead director Todd Boyette is the principal investigator. EvalFest is fostering a community of practice that develops, tests and shares evaluation approaches for science festivals, lending articulation and credibility as to their value to society. EvalFest will help determine how well the goals of science festivals are being accomplished, and what improvements can be made moving forward. Given the outcomes of EvalFest, science festivals can develop best practices in science outreach and create vehicles for making STEM disciplines part of our national DNA.