I carried out my research project in two phases. Phase 1 sought answers to RQs 1 and 2, i.e., it aimed to explore the beliefs that primary and secondary school EFL teachers in Hungary hold about the concepts of differentiated instruction and technology-enhanced differentiated instruction (RQ 1 and its sub-RQs) and to investigate how these teachers describe their practices of these approaches (RQ 2 and its sub-RQs). Phase 1 was based on an exploratory sequential design, the aim of which was “to first explore qualitatively with a sample in order to determine what questions to ask, what variables to measure, and what people to ask” (Creswell, 2015, p. 546). As such, Study 1 served to generate themes that could be then operationalised into variables investigated in the questionnaire of Study 2. Based on this design, I first conducted an interview study with 9 Hungarian primary and secondary school EFL teachers (Study 1) to identify variables with regard to RQs 1 and 2. The results of Study 1 were used to construct the items for the large-scale questionnaire study involving 212 primary and secondary school EFL teachers (Study 2), which sought to answer the same set of questions (RQs 1 and 2 and their sub-RQs).

Phase 2 aimed to take a closer look at some primary and secondary school EFL classes to investigate how teachers use technology in their lessons for DI purposes, and, ultimately, to identify some common patterns of using technology for differentiated instruction (RQ 3). This phase was intended to be a primarily qualitative and exploratory investigation, using “an inductive, as opposed to deductive, approach to research” by “looking for, describing, and accounting for observed patterns” (Duff, 2008, pp. 30–31). I adopted a convergent parallel design of mixing methods (Creswell, 2015) by conducting three studies (Studies 3, 4, and 5) in a concurrent manner to answer the sub-questions of RQ 3, and, ultimately, to merge and interpret the outcomes of these studies to answer RQ 3. Study 3 comprised semi-structured one-to-one interviews with 5 teachers to examine how they describe their use of ICT for DI purposes and what affordances and challenges they see in using ICT for differentiated instruction (RQs 3.1–3.2). Study 4 was based on the observation of the lessons of the same primary and secondary school EFL teachers to examine what curricular elements of DI are supported with ICT and what affordances of technology for DI can be identified in the observed practices (RQs 3.3–3.4). Study 5 involved a questionnaire administered to the primary and secondary school students taught by the participating teachers. The aim of this study was to explore the students’ perceptions of the technology-enhanced differentiated activities and to examine the relationship between these perceptions and their motivation, language learning experience and self-efficacy beliefs (RQs 3.5-3.6). Finally, the results of Studies 3, 4, and 5 were compared and discussed to answer the overarching RQ 3. A brief summary of the research design is presented in Figure 1, while an overview of the research questions, methods of data collection and analysis is attached in Appendix B.