As both a math tutor and a physics tutor, I have often encouraged my students to watch STEM education videos on Khan Academy because of how consistently relevant, clear, and engaging the content is on that very popular education website.
Last week I watched this YouTube video created by someone who has done experimental research on the effectiveness of using videos to teach science. It makes the claim that, although they play a valuable role, otherwise high-quality science videos can have the disadvantage of not challenging existing beliefs. Consequently, viewers do not pay sufficient attention to the key ideas being taught and therefore do not learn as much as they could.
The video is short and its examples demonstrate the points very effectively so I encourage anyone interested in STEM education to watch it.
Do I plan to stop recommending Khan Academy to the students I tutor? No.
Every single time I have ever worked with a student I have tried to challenge them in some way, often by detecting a false assumption and then guiding them to its illogical conclusions. Students usually remember lessons like that and avoid making the same mistakes in the future. Once faulty ideas have been displaced from impressionable young minds, Khan Academy videos become valuable for reinforcing correct ways of solving problems.