The boys were as nervous as the girls.
Der Bursch = the lad, according to Google Translate. I’m guessing this is either regional or antiquated, or both? I did learn just now from dict.cc that a related word is “die Burschenschaft” (the fraternity), which is another word I’ve never heard in German before now.
Another word that I came across in Fluency Fast track is Laufbursche meaning “errand boy”.
Here’s the German Wiktionary page - Laufbursche.
I also note that according to Wiktionary, both Der Bursch and Der Bursche are valid for the meaning of “lad, boy”.
What’s amazing about that to me is that, even after learning German for seven years now, I still routinely come across seemingly commonly used words that I’ve somehow just never seen before. More and more as I get older, I’ve come to believe that language learning is a life-long effort that simply never ends 
You are right. It is somewhat old fashioned and its probably more used in southern Germany, if at all.
To translate “Burschenschaft” with “fraternity” is correct, but maybe it is noteworthy that the German word has also an old fashioned and also a reactionary / far right ring.
Similarly, “Laufbursche” is not an offical job title anymore.
It is only used in a negative sense:
“Kannst Du mir einen Kaffee bringen?”
“Ich bin doch nicht Dein Laufbursche.”
So, in general, be careful with “Burschen”. 