Why not try to get copies of math textbooks in other languages? In my younger days I lived in Germany and a friend took me to meet his parents. His dad had a German calculus Textbook and I shocked them all when I started to read it aloud to them. No, my German is not that great. It's just that the symbology is, of course, the same as we use in America.
Wouldn't middle school and junior high schoolers be surprised that they could actually read thing out of a foriegn textbook