Sixteen foreign exchange students staying in the Glen Ridge area said “adios” to their host families tonight at a farewell party at the Town Pub in Bloomfield. Most of the students, part of the Academic Adventures program, arrived a month ago, and since then their local lairs — the Glen Ridge train station, Cafe Eclectic and Eagle Rock Lanes — have been filled with the sounds of European accents. Here, a little demonstration of Spanish dancing. The exchange students leave Wednesday. It’s going to be a lot more dull on Thursday.