The WATERS project addresses the need for water education and career readiness by developing and researching a universally accessible, student-centered curriculum that employs Universal Design for Learning (UDL) principles. This approach ensures that learning about water quality, usage, and stewardship is accessible to all students, enhancing their understanding of and engagement with vital water issues. Through hands-on activities, local data, and geospatial analysis, the curriculum aims to increase student interest in STEM careers by exploring watershed-related geographic, social, political, and environmental concepts. Conducted in diverse middle school science classrooms across CA, OR, PA, and VA, our research focuses on the impact of UDL integration on student learning, development of 21st-century skills, and interest in water-related careers. Notably, our findings show that students with disabilities who has access to UDL technologies achieved significantly higher content knowledge scores compared to their peers in the control group, underscoring the effectiveness of tailored educational supports in fostering equitable learning opportunities. Through WATERS, we are preparing a new generation to effectively steward our water resources and pursue STEM careers, ensuring a sustainable future for all.