The first part of this study is making a conceptual tie between three distinct bodies of knowledge: Green Care, Positive Youth Development (PYD), and One Health. Green Care is an organizing construct for various interventions that use nature as a framework. I suggest that a nature-based program which incorporates Animal-assisted and horticulture interventions have the potential to promote positive youth developmental outcomes. The two major tenets of the PYD model are the mutually influential and bi-directional relationship between an individual and their context, and this relationship characteristic of plasticity, the potential for change (Lerner, 2006). Plasticity is viewed as an asset, suggesting that aligning the assets of the individual and their context through [programming] can promote positive development (Lerner, 2006; Lerner, Lerner, von Eye, Bowers, & Lewin-Bizan, 2011). The PYD approach does not view positive development merely as the absence of problem behaviors; rather, it is viewed as thriving, flourishing, and healthy development (Lerner, von Eye, Lerner, & Lewin-Bizan, 2009). Thriving is conceptualized through the growth in the attributes that are termed the 5Cs of PYD: competence, confidence, character, connection, and caring (Lerner et al., 2005). This study makes the argument that a Green Care intervention which includes Animal-assisted and horticulture interventions can promote PYD by increasing the 5Cs. The suggested Green Care intervention utilizes the human-animal- environment relationship. This relationship is also the focus of One Health which recognizes that the health of humans, animals (pets, livestock, and wildlife), and the environment are interconnected (e.g., the One Health Initiative; AVMA; CDC; Zinsstag, Schelling, Waltner-Toews, & Tanner, 2011). As some of Earth\u27s systems are in danger of becoming unstable (Rockström et al., 2009; Steffen et al., 2015) due to human unsustainable development (FAO, 2011), the One Health field is encouraged to invest efforts in prevention (Amman, 2012, Rockström et al., 2009; Steffen et al., 2015). These prevention efforts tie back to the Green Care intervention suggested in this study. The main goal of this study was to examine a presence or change of the 5Cs within children who participate in a nature-based program. 20 children were interviewed for this study, and these interviews were qualitatively analyzed to answer the research questions. The participants in this study are students at Green Chimneys, a special education school which employs nature-based programs for educational, clinical, and recreational purposes. The presence or change of each of the 5Cs domains was found in varying prevalence, in relation to animals. However, none of the 5Cs domains was found in relation to horticulture. The study concludes that the findings in relation to animals can be explained by direct learning (Feuerstein, Feuerstein & Gross, 1997), whereas, employing intentional mediated learning (Feuerstein, Feuerstein & Gross, 1997) can enhance these finding and form them for the horticulture interventions