Since 2017, Jackson State University's (JSU) Minority Advancement through Recruitment and Retention in Science via Outreach Program (MARRS-OP) developed a series of professional development (PD) programs designed for 6th-12th science teachers in under-resourced Mississippi school districts. Due to COVID-19, MARRS-OP's original program design was modified to implement innovative online PD courses, designed to expand and sustain the reach of STEM teaching and learning opportunities -- particularly for lab experiments. The PD topics included science-subject-based courses centered around equity, science, and technology. Tools for assessing MARRS-OP outcomes included a remote readiness screener for data collection, pre- and post-program survey data collection, and teacher presentation reviews. Despite an array of challenges, teachers reported statistically significant increases in confidence in their ability to teach biology and physics. Teachers also saw value in remote PD, as it provided the ability to experience virtual instruction from their students' perspective, and the opportunity to collaborate with other teachers and expand their network. This article shows that by preparing science teachers to customize approaches for their students, and maintain flexibility, that initiatives such as MARRS-OP can serve as an empowering resource for teachers despite the accessibility and engagement challenges encountered by the sudden shift to online pedagogy.