After 4 years and $4 worth of raises from my current employer, I'm going back to college to persue an advanced degree in what im passionate about. This company is awful and therefore has a ridiculously high turnover rate. HR and management was not happy to hear I was leaving. They bluntly demanded a letter of resignation so I sent them this as a 2 weeks notice. I would burn bridges, but letters of reference are critical in my area..