In this paper, we argue for the use of digital technologies in making original sources more accessible to students. We present a teaching scenario outlining a use of GeoGebra to ‘unpack’ a selected proposition from Euclid’s Elements. We discuss potential benefits of applying digital technologies through Duval’s (2006) framework of semiotic registers, through Trouche’s (2005) framework of instrumental genesis, and a use of Barnett and colleagues’ (2014) approach of guided reading. The combination of original sources and use of digital technologies appears to be a somewhat overlooked area in the HPM research, not least in terms of empirical investigations. Yet, in this paper we lay down the theoretical bricks for such further investigations.