... I suppose what is also easier it to assume that sheets can be reused locally. Someone suggested making dinosaurs and other toys out of cardboard. These sheets can also be used in crafts such as dioramas, masks, or as inserts to stiffen fabric crafts. They can also be used as dividers in filing, or to make signage ... I'm brainstorming here. :) That actually seems way more economical than trying to recycle them. (These sheets are easy to cut with scissors, sew with thread and keep folds well.)
Hi Nathan - It's possible that the sheets will have to be shipped to recycling plants outside of the country they're being used in, though recycling facilities do exist.
The material I'm imagining is the sheet material common in hobby building and design modeling. My impression is that this type takes to recycling better than other forms such as Styrofoam, though I will do some more research this weekend and share what I find.