The present case study is inspired by preliminary observations of a young adolescent's use of private speech within pretend play to develop disciplinary knowledge in the home domain. Using audio-recordings of the learner's pretend play as a starting point, followed by informal conversations with her, the parent-as-researcher investigates the learner's choice and use of mediational tools and texts as she engages with disciplinary contents and navigates disciplinary challenges. The findings indicate that the informant uses a combination of mediational tools and texts, both digital and non-digital, as part of her disciplinary literacy practices. Interestingly, she also uses vocalized private speech within the privacy of her pretend play to develop, extend and practise her disciplinary language and literacy skills. It is argued that the informant authors her personal learning space as an empowered and an increasingly autonomous learner by choosing and using different mediational tools and texts, each of which has its own affordances. It is also argued the informant's choice and use of each of the mediational tools and texts available to her are shaped and constrained by the physical environment which she inhabits.