hi Prof, welcome.

Sorry, I had not personally encountered this at all. But I see Urban Dictionary gives two janus meanings:

http://www.urbandictionary.com/define.php?term=scosche

1. scosche 102 up, 14 down
A small amount, a tiny bit
Move a scosche

A scosche of food

A scosche of work left

2. scosche 7 up, 102 down
a large amout of bull crap
that was quite a scosche of beer

would you like a breakfast scosche?

I'd like a scosche of doughnuts

fwiw, the crowdsource response gives your usage the popular nod. Can you give a context of how you have heard it?