I teach business. I teach about management. I teach students and students teach me. One lesson I talk about is people do what the boss does. Students do what the teacher does. If the teacher is not motivated, the students aren’t motivated. If the teacher sits down and doesn’t interact with students, the students sit down and don’t interact with each other or the teacher. I often see teachers showing a video in class. While the teacher shows the video, they sit down and work on other things. Students see this and pull out their phones or other work and don’t pay attention to the video.
Might I suggest standing next to the screen while the video or presentation is being shown? Your presence of being up and next to the screen will non-verbally show students you are interested and invested in the video. I often pause and start small discussions about videos. This engages the students. It is a small thing to do. It makes a big difference.