The goal of this project is to study how the integration of an online curriculum, scientist mentoring of students, and professional development for both teachers and scientist mentors can improve student outcomes. In this project, teachers and scientist mentors will engage collaboratively in a professional development module which focuses on photosynthesis and cellular respiration and is an example of a student-teacher-scientist partnership. Teachers will use their training to teach the curriculum to their students with students receiving mentoring from the scientists through an online platform. Evaluation will examine whether this curriculum, professional development, and mentoring by scientists will improve student achievement on science content and attitudes toward scientists. The project will use mixed-methods approaches to explore potential factors underlying efficacy differences between in-person and online professional development. An important component of this project is comparing in-person professional development to an online delivery of professional development, which can be more cost-effective and accessible by teachers, especially those in rural and underserved areas.