I came across this wonderful documentary on the topic of garbage on YouTube and I HIGHLY recommend it to you.
As the title indicates, the film shines a light on where trash ends up, as well as how people at the end of the waste management chain in many countries live in and off the waste their communities produce. This particular real life story is set in Nicaragua.
Would you be able to work in a dump? I would find it pretty tough.
Check out my blog for other YouTube documentary recommendations on how waste affects communities around the world.
Also, remember that you can also find lesson plans and songs to use in class.