gangsterlicious_scholar

I apologize if this question has been asked before, but I am stumped. I need suggestions on how to quit an agency job quickly yet with poise. I start my masters program this September, however, I am taking a little trip to Ireland before the start of the quarter. I guess what I am struggling with is do I tell the company the truth, that I will be starting grad school? Or make up an excuse? Or just resign without any notice since I am an at-will employee?