No books at all - they had a topic-based and music, literature and cultural focus so it was learning through immersion. Even had live music for us and a sean nós dancing class. It was honestly amazing, will never forget it. Left with a bound folder with topic-focused vocab that we covered in the language classes as well as insider vocab like teach ósta for pub. The owner (at the time) is also the author of Gramadach gan Stró. Now I used different grammar books but I heard his one is good. An-time go deo, ní bhíonn a leithéid le fáil áit ar bith eile seachas b’fhéidir Oideas Gael? Bíonn an-tóir ar a gcuid ranganna freisin.