The famous trolley problem is one that I suspect all IB Theory of Knowledge classes consider during the year.
Here are a variety of useful videos that address it. I particularly like the first one, which is really the first in a series of four from the PBS (they all automatically start when one ends), and the second from the BBC:
Here are a couple of lighthearted additions to that list:
A runaway trolley is about to kill philosophy professors who invent trolley problems. Will you divert it? pic.twitter.com/mlfi0mydlZ
— Peter Krantz (@peterkz_swe) August 14, 2016
TED-Ed has released a new lesson and video on the famous Trolley Problem: