The objective of this research was to enhance the life and career skills of the students at Khon Kaen Wittayayon School in Khon Kaen Province by utilizing participatory action research methodology that involved the development of three aspects: (1) changes in the expected and unexpected outcomes from the implementation, (2) learning gleaned from the implementation process for the researchers, co-researchers, and school, and (3) the theoretical knowledge grounded in the specific context of Khon Kaen Wittayayon School. The target group for the development of the research was students in Grades 10-12 at Khon Kaen Wittayayon School, with a total of 268 individuals. The research involved 2 cycles and was comprised of 10 steps. The results of the study indicated the following: (1) there were improvements in both expected and unexpected outcomes, both in cases in which the jointly developed development guidelines had been followed and in cases, in which the expected life and career skills had been developed; (2) the researchers, co-researchers, and school learned together about the effectiveness of collaborative work, which had helped everyone to see the inefficiency of the individual work that had been carried out in the past; and (3) the theoretical knowledge gained from the implementation, which explained the relationships between expected changes and the driving forces behind those changes, the barriers to change, and the strategies for overcoming those barriers.