This guide will delve into the current landscape of state-funded STEM-focused internships and work-based learning opportunities available to high school students in Massachusetts. By examining these programs in detail, the aim is to highlight the specific learning opportunities they provide, the types of industry partnerships they promote, and the skills and experiences students gain through participation. Additionally, this guide will explore the offerings of Regional STEM Networks across Massachusetts, assessing how these networks support students in a variety of cities and town and the disparities that may exist in terms of access and quality. The guide provides a comprehensive overview of the strengths and limitations of each STEM-focused initiative, identifying best practices and successful models that can be replicated and scaled. This guide will showcase examples of effective collaborations between schools, employers, and higher education institutions, and how these partnerships can benefit students. Furthermore, this guide will point out critical areas for growth, emphasizing the need for a more coordinated and inclusive approach to STEM work-based learning experiences across the Commonwealth. The guide also offers policy recommendations aimed at bridging the gaps in access and quality, such as ensuring students have access to paid internship opportunities, enhancing transportation options for rural students, standardizing quality, and fostering statewide collaboration among stakeholders. The goal is to provide policymakers, educators, and industry leaders with a full understanding of the state-funded STEM internship and work-based learning landscape as well as recommendations for system improvement.