As a Chemistry/Physical Science teacher, my initial thoughts concern the development of simple laboratory experiments that the students can perform which will allow them to directly observe how CO2 acts as a greenhouse gas. Perhaps, the procedure could be extended to also show how dissolved CO2 can modify the pH of oceans. 

My initial thoughts regarding evidence of climate change in my students' own communities are focused on the fact that Smyrna, Delaware is low-lying and only about 10 miles from the Delaware Bay. Maybe, some students have been directly affected by flooding, know others in this situation, and/or would be interested in exploring recorded information that may reflect a worsening trend.