This paper examines enactments of prototyping in a recent experimental effort to introduce ‘Technology Comprehension’ (TC) as a mandatory school subject in the Danish Public School. The overall concern of the programme was to educate young people to become not only users, but makers and analysts of the digital technological society. We adopt a social-theoretical view of prototyping that suggests it has moved well beyond design, and has become part of a broader cultural repertoire. We explore the capacity of prototyping as a site of social knowledge-production, illuminating prototypes as instruments of experimentation, epistemic negotiation, and civic participation. We analyse two prototypes: 1) an artefact that was the outcome of a pupil’s work in a TC lesson; 2) an experimental lesson plan called ‘App Design’ put to use by a teacher in a series of 5th grade TC lessons. Attending to how prototyping is performed in the pupils’, teachers’, and subject matter experts’ making, demoing, testing, and iterating on ‘first type’ tangible and material artefacts–prototypes. Prototyping in the trial programme can be understood as the rehearsal of chaotic conditions, in the teacher-pupil relation, and in the pupil-world relation. Prototyping can absorb the seeming impossibility of bridging ‘theoretical’ and ‘practical’ knowledges, and make new social and material agencies arise. The trial of TC seems in this light as much as an experiment in rendering social relations and knowledge-making, open-ended and experimental as it is an experiment in cultivating that exact attitude towards technology, but also towards societal affairs and knowledge-production.