Educational trail of Regional centre for waste management (RCERO) is a landscaping project surrounding the regional waste management facilities. It has eleven theme points that educate visitors about types of materials, recycling and re-use of waste.

At each of the theme points, prostoRoz presented a different type of waste by making an instrument out of it. That enabled visitors to get to know and experience waste in a different form - by listening to the sounds and tones produced by various materials.

The Chamber of Architecture and Spatial Planning of Slovenia awarded RCERO project, which includes the educational trail, with the Golden Pencil award in 2017 for best architectural project in Slovenia. The jury argued that the project spreads social awareness on how to manage waste and brings up sustainability issues in a playful way. They appreciated the simplicity of the project, the interaction with materials, efficient use of colour and graphics and a humorous approach to a complicated and technical subject.

The instruments were designed together with Samo Kutin, a musician and instrument maker. Some elements were graphically enhanced by Studio Botas.