I prefer teaching lessons via webcam as opposed to live, in-person lessons, especially for kids.
The reason for this is that, because the child's view is restricted to my hands, their concentration is at a much higher level. One explanation is the modern child's sense of comfort with a video screen of any kind, television, computer or phone. Today's kids are used to staring at a screen and having that screen receive their undivided attention.
With less visual distractions, the child learns more quickly and has better focus.
The child's perception is also limited to the sound of my voice, which results in additional absorption of the rather complex ideas of beginning piano and music theory.
You'll find that the child has a more intense learning experience when using the webcam, perhaps due to the natural limitations of the webcam experience: human instinct is to look at the screen and listen, and to focus nowhere else.
While the natural camaraderie of live lessons is always welcome, you will find that webcam lessons are more serious affairs, because there is really nowhere to which the child can escape, so they give in and throw themselves into learning what the hands and voice are showing them.
In live lessons, behavior is sometimes an issue, whereas in webcam lessons, kids are eager and focused and ready to learn, and there are never any behavior problems.
If you're looking for a great piano teaching device, whether you are a teacher or a student, I suggest lessons via webcam.
ZOEN teacher John Aschenbrenner teaches piano to all ages, and specializes in children and those with special needs.