This paper reports on the incorporation of an embedded tool within a virtual classroom environment (ClassSim) and the use of this by pre-service teachers as they engage with the software. The classroom simulation reported on in this research was developed to provide pre-service teachers with a safe virtual environment in which they are able to explore 'authentic' and practical classroom scenarios. The embedded tool, referred to as the 'Thinking Space', was developed to support pre-service teachers in capturing their reflections about the complex role of a teacher as they move through the experience. Encouraging reflection has long been acknowledged as an important strategy in the development of new understandings. Our trials of the software have shown that pre-service teachers have used the tool to reflect upon issues within the classroom, articulating their rationale at decision points and to identify underlying influences that affect their use of the classroom simulation (ClassSim) and their understandings of the role of a teacher. Our findings also reveal that the 'Thinking Space' provides a framework in which pre-service teachers are able to build connections between the theory of their pre-service training and practical experiences.