Active participation in Moderate to Vigorous Physical Activity(MVPA) is the indicator of healthy development for adolescents. However, Korean adolescents’ MVPA have continuously declined, and Korean adolescents have lower levels of MVPA compared to adolescents in other countries. Considering this issue, the purpose of this study is to examine the effectiveness of SPARK M-SPAN program to promote adolescents’ MVPA in P.E. classes and to understand how the promotion of adolescents’ MVPA occurs. To collect data, this study used Sequential Mixed Method and GT3X accelerometers. A total of 168 adolescents (84 in an experimental group and 84 in a control group) participated in this study for the quantitative data analysis, and six students and a teacher were interviewed for the qualitative data analysis. Paired t-test showed that students in SPARK P.E. classes experienced the significant decreases of sedentary behaviors(-339.6 sec) and low intensity P.A.(-96.9 sec) at p<.05 and the significant increases of moderate(+99.3 sec), vigorous(+252.4 sec), and very vigorous intensity P.A.(+84.7 sec) regardless of gender difference at p<.05 except for female students’ moderate intensity P.A.. The qualitative data analysis showed that SPARK classes gave students positive learning environments and led them to experience enjoyment and achievement-orientated learning Key teaching strategies of SPARK program and future research suggestions were provided in the discussion section.