Studies show that Professional Development (PD) can be helpful in supporting teachers’ professional growth and lead to positive changes in the classroom. However, many teachers feel that the PDs they attend are not helpful. This research consisted of three individual case studies followed by a cross case analysis. This study incorporated three science PDs that focused on the implementation of the Next Generation Science Standards (NGSS). For each of the PDs there were two participant pools. The first pool of participants consisted of all willing participants, and the second pool of participants was a subset of the first pool. The first pool of participants received a link to a pre-PD survey to learn about their self-efficacy about teaching science. They also completed at least two check-ins for each day of the PD to measure their level of engagement and learn about what they found meaningful. The second pool of participants were interviewed at the conclusion of each PD. These interviews aimed to get an in-depth understanding of their thoughts and opinions about science PDs. Moreover, the interviews helped identify the features that elicited teacher engagement and encouraged classroom implementation. This study showed that there are several science PD features that educators find advantageous. The three overarching features that were shared across all case studies were: new learning, experiential learning, and collaboration. Overall, this study shares important NGSS PD features that can be used by PD facilitators, school administrators, and district leaders to plan effective PDs for science teachers.