A university design research unit, the PolyPlay Lab, was commissioned by a Hong Kong (HK) educational science, arts, and crafts kit company to investigate practices of environmental education (EE) early primary school stakeholder, market , technology, and symbolic elements. Weaving design, play, and STEAM (Sci-ence, Technology, Engineering, Art, Maths) education principles, the project determined tactics to stimulate children's environmental consciousness. Findings informed the design of EE product-service systems (PSS). Deliverables were tested in school with 150 children (ages 6 to 7) and 11 teachers. This paper describes the research process and its findings, which suggest there is value in leveraging: 1) experimental research through design and play; and 2) art's playful (or play's artful) whimsicality as effective strategies to design innovative EE PSSs to foster inner city children's environmental sensitivity.