350.org

Depending on what's happening in the community during the semester, the class might participate in marches that relate to environment and/or social justice. One year we marched with 350.org, a non-profit that educates about the elevated levels of carbon dioxide that's in the air and how that effects everyone worldwide. 

"And what does this 350 number even mean?

350 is the number that leading scientists say is the safe upper limit for carbon dioxide—measured in "Parts Per Million" in our atmosphere. 350 PPM—it's the number humanity needs to get back to as soon as possible to avoid runaway climate change."
-350.org's official website