The COVID-19 pandemic accelerated the shift towards e-learning and distance education, increasing demand for flexible and customizable online programs. Research emphasizes student learning engagement as a key determinant of online learning quality and outcomes. Teaching presence, a core component of the Community of Inquiry framework, is crucial for connecting social and cognitive aspects of online learning and reducing teacher-student distance, thereby positively impacting student engagement. However, challenges remain in ensuring quality learning experiences in distance education, including a lack of interpersonal interaction and effective teaching support. This study addresses the under-researched area of teachers' perceived teaching presence in Vietnamese tertiary online distance education programs by exploring how teachers organize their pedagogical practices in an online English-language course at a Vietnamese higher education institution. Teaching presence, encompassing design, facilitation, and direction of cognitive and social processes, is a significant determinant of student satisfaction, perceived learning, and community sense. It's crucial for connecting social and cognitive components, decreasing teacher-student distance, and positively affecting student engagement. While prior research highlights its importance, less is known about how teachers perceive and enact teaching presence in the specific context of Vietnamese tertiary online distance education. This study aims to address this gap by exploring how teachers design and organize teaching and learning in online distance courses, facilitate discourse, deliver content, and assess student learning.

Existing research underscores the significant role of teaching presence in online learning environments. Studies have demonstrated strong correlations between teaching presence and student satisfaction, perceived learning, and overall success. Furthermore, research has explored teachers' mixed perceptions of teaching presence in various online learning contexts, including mainstream programs. However, a gap exists in understanding how teachers perceive and enact teaching presence within the specific context of Vietnamese tertiary online distance education. This study aims to fill this research gap by examining teachers' practices and perceptions in this under-researched setting.

This study employed a bounded single-institution case study design to investigate teacher practices in a Vietnamese higher education institution's online distance education program. Convenience sampling was used to recruit five teachers from various disciplines with extensive experience in online distance education. Data were collected through five semi-structured individual interviews conducted via Zoom, recorded, transcribed, and analyzed using thematic analysis with NVivo 12 software. The analysis focused on three dimensions of teaching presence: design and organization, facilitation of discourse, and direct instruction. The thematic analysis involved familiarization, coding (inductively and deductively using Garrison et al.'s framework), theme aggregation, refinement, and member checking to ensure trustworthiness and rigor. The researchers employed Lincoln and Guba's criteria for trustworthiness (credibility, dependability, confirmability, and transferability) and incorporated reflexivity to account for their insider perspectives. Data analysis was informed by contextual data analysis of interview excerpts and direct quotations from teachers.

The analysis revealed agentic practices employed by teachers in online tertiary distance education. Regarding design and organization, teachers largely adhered to pre-designed course outlines and structures provided by the institution, with lectures divided into sections, quizzes designed to assess understanding, and a structured ten-week schedule involving online video conferences and weekly tasks. They emphasized pre-course training for students on learning approaches and technology. In facilitating discourse, teachers used diverse interaction channels, including discussion forums, video conferences (Zoom), and social networking groups (Zalo), encouraging student participation, monitoring discussions, and providing prompt feedback. Teachers actively managed online discussions, prompting student responses and addressing concerns. In direct instruction, teachers delivered content during video conferences, providing feedback and addressing student queries. Some teachers used a flipped classroom approach, providing pre-recorded lectures and using various methods (LMS, email, Zalo) for providing feedback. Assessment methods included end-of-unit and end-of-chapter tasks, quizzes, end-of-course examinations, and assessment of student participation in discussions and video conferences. Teachers valued student reflection and engaged in their own reflective practice to improve their teaching.

The study reveals a prominent teacher agentic online teaching presence, showing how teachers adapt to the structured format of the online distance courses while proactively utilizing their agency in facilitating discourse and direct instruction to enhance student engagement. The findings align with previous research highlighting the importance of teaching presence in student online learning, showing a correlation with student satisfaction and learning. However, the study reveals a stronger emphasis on facilitating discourse than direct instruction compared to some previous research. This difference is likely due to the unique characteristics of the online distance education program, which relies more on asynchronous learning through the learning management system. This research emphasizes the importance of integrating social, cognitive, and teaching presence to improve student motivation and learning experiences.

This study contributes to the understanding of teaching presence in online distance education by demonstrating how teachers use their agency to enhance student engagement and learning experiences. While adhering to structured course designs, teachers effectively employed diverse strategies to facilitate discourse, deliver content, and assess learning. The findings underscore the importance of acknowledging and supporting teachers' agency in online distance education and suggest focusing on professional development opportunities that integrate social, cognitive, and teaching presence to improve student engagement and prepare teachers for diverse teaching and learning modes.

The study's limitations include the potential lack of representativeness of the participants, as they may not fully reflect the perspectives of teachers across all disciplines within online distance education programs. Future studies could investigate teachers from other disciplines, such as science and technology. The absence of teacher observation and reflective practice as data sources is another limitation. Future research could incorporate these components to provide a more comprehensive understanding of teachers' agentic adaptations and the challenges they encounter.