This introductory article frames the special issue in terms of the focus and the scope of the topics involved. The central theme of the special issue is the development of teachers’ assessment literacy in enacting formative assessment in the language classroom. The pervasive issue of misappropriation of the formative assessment label is discussed, and the need for conceptual clarity about FA is emphasized as a basic condition for developing competence for the enactment of FA in the classroom.

1. Formative Assessment

This chapter describes the process and function views of formative assessment, and how FA can be summarized into a table. It explains that an instrument such as a well-designed test can be used formatively and that FA does not stipulate a particular format for evidence gathering. It also highlights that FA can be done by teachers, learners, and their peers, with the main responsibility for enacting formative assessment resting with the teacher inside the classroom. The real theme of the special issue is the development of the teacher’s assessment literacy for formative assessment.

2. Assessment Literacy

This chapter discusses the challenges faced by teachers in integrating formative assessment (FA) into the teaching and learning process. Efforts have been made to develop practical tools for teacher education, but most efforts on assessment literacy have not reached the classroom. The chapter also explores the conceptualizations of assessment literacy and models describing and explaining teacher assessment literacy. Andrade et al. (2021) concluded that FA is essentially co-regulated learning.

3. Developing Teacher Assessment Literacy for Formative Assessment

This chapter discussed the challenges of developing teacher assessment literacy for formative assessment, including the lack of preparation in teacher education programs. It also highlighted the importance of teachers as reflective practitioners and the involvement of all stakeholders in the learning process. The chapter mentioned the "starter kit" approach and the use of concrete tools to scaffold teacher development of assessment literacy. It emphasized the need for gradual and incremental implementation of formative assessment practices and the importance of providing cost-effective heuristics. The chapter concluded that developing teacher expertise in using formative assessment is a difficult endeavor, and more research is needed in this area.

4. This Special Issue

This special issue includes 10 articles and 15 authors from around the world, focusing on the development of assessment literacy for classroom-based formative assessment. The articles address a variety of topics related to assessment literacy, including teacher professional development, assessment identity, teacher feedback literacy, assessment difficulty estimation, and learning-oriented assessment practices. The findings highlight the ongoing need to develop teachers' assessment literacy, while also providing valuable insights and suggestions for improvement. Overall, the special issue presents timely and exciting findings about the continuous development of teacher language assessment literacy.