a) your 12 year old son finds a major (and very obvious) historical error in the first ten minutes of the first episode (the teacher mixed up the geographical locations of Upper and Lower Egypt)
b) you both find the teacher's style quite boring (even though he dressed up in costumes and used funny accents which was supposed to make it "fun" and "interesting") and then...
c) when skipping to a different segment to try to get a sense of other parts of the course you stumble across a segment on the Middle Ages that devotes a great deal of its half hour lecture on Life in the Middle Ages describing a hypothetical superstitious activity on the part of a monk.
UPDATE: My mistake. The above part was about the Dark Ages in a section entitled "The Early Christian Church"
d) Finally, while looking over the list to see if there's anything more to the Middle Ages, you happen to notice that an upcoming segment is entitled "The 1300s - the Age of Despair."