We investigate common objects as material support for programming workshops for children and adolescents in non-formal learning contexts. To this end, we engaged in a one-year participatory design process with a facilitator of programming workshops. Based on observations of workshops and interviews with the facilitator, we mapped out their artifact ecologies to investigate how the multiple artifacts and common objects were orchestrated by the facilitator and then adopted by the participants of the workshops. Building on these findings, we explored the development of a collaborative teaching tool, MicroTinker, through a participatory design process with the facilitator. This paper presents the results of our analyses and shows their constructive use to design technology in a non-formal learning setting.