Narration in promotional ads for this series says, "Darwin's theory of evolution says that the fittest thrive..." In fact, Darwin never said this, nor does it appear in his writings. To Darwin, "fit" meant "best adapted." The phrase "survival of the fittest" often associated with Darwin was actually coined by Herbert Spencer, a contemporary of Darwin's who was a popular political writer.
In the segment "Dead Eye", the title card states that the incident took place in 1993, yet after the gym teacher is impaled through the eye on the javelin, one of the students takes a picture with his cellphone. Cellphones with photographic capabilities didn't exist in 1993.