In light of the adoption of the UN Convention on the Rights of Persons with Disabilities (2007) as well as increased immigration and concomitant diversity, schools in Germany are addressing the challenge of educating learners in increasingly heterogeneous settings. Given the status of English as a foreign language (EFL) as a core school subject as well as a necessary skill for participation in the global community, the need to prepare future second language teachers to address this heterogeneity is of critical importance. To address this, a blended learning seminar for pre-service teachers (PSTs) in EFL was developed within a community of practice. The concomitant research focuses on an examination of the PSTs’ attitudes towards inclusion, their beliefs towards language learning, and the development of their reflective competence. Given the exploratory nature of this research, a mixed-methods study was designed to triangulate data from multiple instruments to analyze these items, and the ways in which they develop over the course of a semester. Using a pre-/post-intervention questionnaire, descriptive statistics and qualitative content analysis were carried out to understand the ways in which attitudes towards inclusive EFL, beliefs about inclusive language learning, and reflective competence for inclusive EFL changed over time.