To solve the wicked problems of sustainability, education for sustainable development (efsd) that raises the young generation to become change agents is necessary. For this purpose, fieldtrips that educate students in the real world about other stakeholders are effective, but since sustainable issues do not have clear solutions, cooperative learning (cl) in which students learn from each other is useful. The purpose of this study is to clarify the influence of the learning process on learning outcomes and their influence on learning objectives in real-world efsd using cl. A hypothesis model consisting of seven hypotheses was set up, and a questionnaire survey of high school students who participated in the real-world efsd was conducted. Results of the structural equation modeling of data from 2441 respondents supported all seven hypotheses. Implicit learning as a learning process promotes knowledge acquisition as a learning outcome, while explicit learning enhances self-efficacy. Although knowledge acquisition promotes citizenship development as the learning objective of efsd, self-efficacy does not promote citizenship development. Self-efficacy affects knowledge acquisition more than implicit learning. This study contributes to efsd research by clarifying the difference in the effects of the learning process. 2021 By the author. Licensee mdpi, basel, switzerland.