EAST MARLBOROUGH — Unionville High School students are participating in a student exchange partnership with students from the Otto-­‐Hahn-­‐Gymnasium, located in Gottingen, Germany. The 20 German students, all high school age, are staying with UHS students from Oct.  20 through Nov. 4. Traveling with the students are the Otto-­‐Hahn High School Principal and an English teacher from the...