For over 15 years, Cameron University has conducted NanoExplorers, a ten-day residential STEM academy designed to introduce high school students to nanotechnology through materials science–centered, hands-on learning. The program emphasizes nanoscale structure–property–performance relationships using experiential learning modules in nanoparticle-based solar cells, superconducting materials, polymer nanocomposites, optical nanomaterials, DNA electrophoresis, and robotics. Students engage in authentic materials processing, device fabrication, and basic characterization while developing scientific communication, problem-solving, and teamwork skills. Program effectiveness was evaluated through participant surveys and longitudinal tracking of academic pathways over a three-year post-academy period. Results show that more than 50% of participants subsequently enrolled in STEM majors at the college level, with sustained participation by women and students from underrepresented minority groups. This paper presents the academy structure, representative nanotechnology learning modules, assessment methodology, and educational outcomes, demonstrating how immersive, materials-focused programs can contribute to strengthening the STEM talent pipeline and preparing future materials scientists and engineers.