Plannning for an absence is harder work than planning for a normal class. How do you leave clear instructions?
With a video, students get the instructions from you, not from an explanation sheet. They hear your voice, your inflection, and your description as they normally would.
After a five-minute description, they can jump right into working, which means the time is more productive.
From the creator:
Teacher-produced screencasts help my students make progress regardless of where I am physically located. I can be a few feet or a few hundred miles away from the classroom and still have an impact on the learning taking place. I like to call it "outsource yourself to yourself" since only you can make the best clone of yourself for every student!