This study examined United States (U.S.) K-12 science teacher interactions with parents during Next Generation Science Standards (NGSS) reform following teachers' professional development (PD) participation, as well as parent accounts of understanding and support for NGSS. Fourteen teachers and 15 parents completed an online surveys and phone interviews. Themes, based on coded data, were constructed to represent relationships between teachers and parents during NGSS classroom implementation post-PD. We found that parents were generally unaware of NGSS and not well-informed about the changes the new standards brought to their child's science classrooms. Despite parents' lack of NGSS understanding, parents generally gave positive feedback about teachers' science instruction. However, parents expressed concern about their child's ability to transition between grade levels and subjects, the lack of an aligned textbook and homework assignments, and confusion with how to help their children at home in preparation for assessments. The results of this study suggest that it is important for school districts to inform parents adequately about the new NGSS curriculum and its implementation. While this study took place in the U.S. and pertains to NGSS, the findings are broadly applicable to teacher development and communications with parents during standards reform, regardless of country.