In the communicative process, the introvert personalities display negative influences on foreign language acquisition. However, teachers' scaffold can increase introverted students' willingness to venture into new ZPD and go through a transformation. Despite the obvious necessity of supporting and assisting shy individuals to expand the scope of their social experiences and realize their personal potential, there is a knowledge gap in the field of "supportive strategies for lowering the threshold of new ZPD for introverted students". To fill in this gap, we conducted a project-based case study in the setting of a high school in China, and employed the method of action research to document its operating procedures and specific supportive strategies. The results proved our two hypotheses that teachers' scaffold can lower the threshold of ZPD and that the flow experience can serve as a trans-formative power of intrinsic motivation. This study is a pilot experiment and will be generalized to more follow-up experiments.

Based on social constructivism, Project-based Learning (PBL) is a student-centered teaching model built to address complex and challenging authentic problems, in which students' co-construct core knowledge and apply the knowledge. PBL has obvious advantages over the traditional teacher-centered model in students' gains in academic achievement, problem solving, interdisciplinary and teamwork. This review discusses principles of the implementation of PBL model, a case study, tested effectiveness as well as challenges. The conclusion is that PBL can be a solution to nurturing self-driven all-round students.