I was just using this video in my class and noticed a major discrepancy.  When he brings what he calls the north pole of the magnet near the compasses four of them point toward it.  He explains that the other one has been inverted by a powerful magnet.  The problem is that compasses point toward the south poles of magnets as explained in the textbook during the discussion as to what type of magnetic pole the earth's magnetic north pole is.  Either he is misidentifying the magnet, or only one of those compasses is working properly.