>There are all valid questions (and not the only ones).
To me, those would be valid questions if we proposed Sal Khan -- and only Sal Khan -- to become the official & approved math video for all students which means we ban every other alternative teacher (virtual or in-class) teacher as a choice. Nobody is proposing this.
Even if (many) viewers don't like Khan (dislike his voice, his handwriting, whatever) and are still confused by his presentation, it's irrelevant because the underlying problem still remains: the local person that happens to be physically present in that classroom may be a terrible teacher for lecturing the students.
Therefore, optimize the lecture portion (the 1-way communication phase) by finding the best virtual teacher for the topic. This means 2 different children in the same classroom may be watching 2 different video teachers at the same time. (The in-class teacher can even help the student find a presenter that resonates.)
The remaining classroom task for the (possibly terrible) teacher is isolated to interactions like answering questions. The 1-on-1 interaction is the higher value phase of learning. The lecturing portion where many teachers drone on in a monotone voice and students are bored and tune out is the lower value phase.
Your point is good, but there are some issues with it.
The person who is there might be bad, but in person means that person gets real time feedback on if the student understands. This factor alone makes not so good teachers better than a video of the best teacher.
If Khan is not the only teacher that means the student needs to figure out which teacher is a good one. There are too many potential great teachers to wade through them all.
Then there are great lectures who will teach you something wrong. I don't care how great you are at presentation, if you are teaching the world sits on the back of a giant turtle you shouldn't teach. This example seems trivial but for a subject the student doesn't know how are they to know the teacher is right?
To me, those would be valid questions if we proposed Sal Khan -- and only Sal Khan -- to become the official & approved math video for all students which means we ban every other alternative teacher (virtual or in-class) teacher as a choice. Nobody is proposing this.
Even if (many) viewers don't like Khan (dislike his voice, his handwriting, whatever) and are still confused by his presentation, it's irrelevant because the underlying problem still remains: the local person that happens to be physically present in that classroom may be a terrible teacher for lecturing the students.
Therefore, optimize the lecture portion (the 1-way communication phase) by finding the best virtual teacher for the topic. This means 2 different children in the same classroom may be watching 2 different video teachers at the same time. (The in-class teacher can even help the student find a presenter that resonates.)
The remaining classroom task for the (possibly terrible) teacher is isolated to interactions like answering questions. The 1-on-1 interaction is the higher value phase of learning. The lecturing portion where many teachers drone on in a monotone voice and students are bored and tune out is the lower value phase.