Background: Thailand is rapidly transitioning into an aging society, creating an intergenerational caregiving gap that strains existing support systems. Objective: This study evaluated the effectiveness of “Young Care,” a community-based intervention designed to enhance youth knowledge, attitudes, and caregiving practices (KAP) toward older adults. Methods: A two-day structured training was conducted in Maha Sarakham Province in 2023 using a pre-post mixed-methods design. Middle and high school students participated in lectures, multimedia sessions, and experiential learning activities related to caregiving. Quantitative data were collected using validated KAP questionnaires, while qualitative insights were obtained from focus group discussions involving students, older persons, caregivers, and local leaders. Results: Post-intervention analysis revealed significant improvements in knowledge and attitudes (p < 0.001), accompanied by increased empathy, caregiving initiative, and a sense of moral responsibility among participants. Conclusions: The initiative fostered formal partnerships among schools, local governments, healthcare providers, and universities through memoranda of understanding. These collaborations enabled budgetary support and outreach to out-of-school youth, positioning “Young Care” as a scalable, youth-centered strategy to address Thailand’s long-term care challenges.