The Primary Difference Between North Korea and South Korea uses two drawings to show the difference between living in Communist North Korea and Democratic South Korea. It might be a fun little comic to show your students. The comic did get me to look in my archives for resources on North Korea that I've highlighted in the past. Those resources are listed below.
Life Inside North Korea
North Korea v. South Korea Incidence Map
North Korea's Military Parade in Slow Motion
Music from North Korea and Around the World
And for a very quick explanation of why the Korean peninsula is divided, here is a video overview of the Korean War.