In the letter, McCall outlined long, unpaid work hours after the school day ended, unrealistic expectations and a lack of time for planning or basic bodily functions like bathroom breaks.
"The only things keeping me from resigning until now were the love I have for my students, the love I have for the act of teaching, and the heavy guilt I feel for my children being negatively impacted by this in any way: emotionally or academically,” she wrote. “However, I cannot set myself on fire to keep someone else warm."
McCall, who has a master's degree, now lives in Savannah, Georgia, where she waits tables.
She said the hours are shorter and the pay is better.