When I first read the prompt for this post it immediately came to my mind that in order to make someone care about something you have to do two things:
1. show them the current status of the situation to help them understand that something needs to be done
2. show them how this issue will impact them in their daily lives (people are more likely to pay attention when it involves them personally)
In order to achieve these goals, I would first have my students collect the data on the issue or research the current status of the issue to provide a baseline for which they can start to make their own thoughts and formulate their own opinions of the issue. Bringing in real data/community stake holders or having students collect the data makes the whole issue more real to them and therefore, this will also help to increase student engagement and buy in throughout the process.
In order to achieve the second goal, I would have students research (if the data is available) how the issue is projected to change over the course of time and then challenge students to think about how they would be impacted by the issue in the future. This will probably be the more difficult of the two goals to achieve since most high school students do not think beyond the next day in their lives but I also believe that it can be achieved with the right resources. From my 6 years of teaching experience, most of the students that I have had, do want to help with a project that will make a difference in the future. The big question is where are the resources (money and equipment) going to come from in order to make their action project dreams a reality?