In Berlin we have many initiatives trying to work with and for refugees. One of the more famous one is building wooden furniture from recycled wood with them and for them. (CUCULA – Refugee Company for Crafts & Design)
Maybe you can find some circular design building plans and start to do something similar with them. Maybe a bit hard but on this forum we have this:
I also know of a project called ROC21 - they combine openness, sustainability and refugees as well: