The purposes of this qualitative case study were to describe the design and the development of a maker-centered learning environment and curriculum by an interdisciplinary team, and to explore how an after-school program that incorporated Maker education and scientific argumentation influenced middle school youths' attitudes toward science in the Midwestern USA. The researchers conducted pre- and post-interviews with six students from non-dominant backgrounds and the teacher, and also administered attitudinal surveys to the six students at two time points (pre/post). Additionally, the researchers video-recorded each after-school session, observed the level of student participation in each activity, and examined student artifacts. At the end of the program, the researchers administered a program survey to the six students. The findings revealed a number of themes. This after-school program eased the tension from the formal science learning with the playful qualities of Making activities and developed the students' practice of social negotiation, which sustained their liking of science. The Making and scientific argumentation activities provided an opportunity to contextualize STEM concepts and practices, which allowed the students to value science by re-affirming as well as expanding their career choices. The Making and scientific argumentation activities helped boost confidence that, up to that point, had been decreasing in formal science learning contexts. The findings speak to the need for future studies that investigate pedagogy issues in Making after-school programs and also examine equity issues in the opportunities for non-dominant youth to participate in these programs.