When researching the optimal length of videos online, the sources tend to say that 6 minutes is a gold standard and anything up to 13 is acceptable. They suggest that after 13, viewership drops off significantly.
This article suggest that shorter videos are more effective for online learning: https://www.linkedin.com/pulse/research-goldfish-best-practices-determining-video-length-lassoff#:~:text=Study%201%3A%20%22Online,hold%20students%27%20attention.
This article suggests something similar: https://www.iacet.org/events/iacet-blog/blog-articles/short-attention-spans-and-long-term-retention-the-evolution-of-learning-in-the-digital-space/#:~:text=The%20New%20Gold,questions%20anytime%2C%20anywhere.
Moving from a in-class lecture model to an online video model is difficult. These are some tips to help you cut down your videos:
When you are not speaking while recording videos, try not to make noise. That way, you can easily cut silent chunks of your video on Screenpal.
Move your activities to the practice outside of your video. While it may be tempting to move some of your call-and-response strategies from in-person to video, it doesn't often work well.
Chunk your videos by creating shorter videos on smaller pieces of your content.
If you are consistantly thinking about length in your videos, you will get better at it with time.
The Modern Classroom Project shares this video with teachers to discuss video production for teachers: https://www.modernclassrooms.org/blog/building-effective-instructional-videos
This article helps teachers understand pacing and length of their videos: https://www.screenstory.io/blog/educational-video-mastery-crafting-editing-and-teaching-with-impact