Since computer technologies entered the educational domain, a number of metaphors have been introduced in the literature to explain this newly emerged phenomenon to educators in familiar terms. This chapter explores the ways that the conceptualisation of educational technologies as a teaching 'tool' can assist our understanding of the implementation of a new digital technology, the interactive whiteboard (IWB), in teaching children with Autism Spectrum Disorders (ASD). The tool metaphor relates to a socio-cultural concept of a tool mediated purposeful human activity as a unit of analysis in educational research (Vygotsky, 1978). The activity model (Engestrom, 1991) was adopted in this study to focus on the teachers' use of technology. The IWB was then analysed as a teaching tool that can enhance (or hinder) the teacher's pedagogical goals. The chapter then provides a discussion of the use of the IWB in children with ASD using the tool metaphor. The question that we asked was how the tool metaphor can assist our understanding of the pedagogical choices made by a teacher in the process of working with children with ASD. The study demonstrated the usefulness of the tool metaphor for providing insights into what constitutes the effective use of the IWB in teaching children with ASD. The use of the metaphor allowed us to go beyond clinically-based research that has dominated the field of special education, and examine the day-to-day reality of how digital technologies were used in a classroom context with students who have ASD.