This study, based on the participation framework, investigated students’ learning of project design skills, psychological sense of community, the relationship between project design skills and psychological sense of community, and design implications in a learners-as-multimedia-designers learning environment. One hundred and twenty-seven students from a middle school in the southwestern United States participated in this study. The treatment group consisted of students in the multimedia classes while the comparison groups consisted of students from the Talented and Gifted (TAG) classes and regular classes. Both quantitative and qualitative data was collected through Project Design Questionnaire, Concept Mapping survey, Design Task Ranking survey, Psychological Sense of Community in the Classroom Scale (PSCC), open-ended questions, interviews and classroom observations. The results from the pretest and posttest data indicated that students in the learners-as-multimedia-designers classes have developed project design skills such as awareness of audience, research, and presentation, and maintained high levels of interest and mental involvement. However, they did not regard evaluation and revision as a critical task and showed variations in their planning and collaboration tasks. The findings also showed that students in the treatment group demonstrated significantly higher sense of psychological sense of community than students in the TAG classes and regular classes whereas students in the TAG classes and regular classes did not differ significantly from each other in their psychological sense of community. Quantitative data also showed that there were significant correlations between some design tasks (audience, presentation, and collaboration) and psychological sense of community. The findings also indicated factors like selecting authentic group projects, providing facility access, and training interpersonal skills for group projects could help promote the learners-as-multimedia-designers environment during its implementation. This research implicated that teachers should create a classroom environment that engages students in collaborative constructive investigation as in the learners-as-multimedia-designers environment.