It's only natural to get curious about how much your coworkers are making, but there is a fine line between being nosy and literally opening up the envelope with their paycheck in it. Albeit, this employee was young, but that doesn't excuse her behavior… She was in college but was working for OP, at a tanning salon in her free time, trying to make some extra cash on the side. Being the snoop she was, she opened up everyone's envelopes to see their pay. Don't try this at home, you WILL get fired…