LAWRENCEVILLE, Ga. (CBS Atlanta/AP) — A spokeswoman for Gwinnett County schools says one teacher resigned during an investigation into third-grade teachers who gave students math homework with word problems about slavery.

Sloan Roach says an investigation into a personnel matter involving four teachers at Beaver Ridge Elementary wrapped up Tuesday. She says the school system accepted the resignation of one teacher during the course of the investigation.

One of the questions on the homework assignment asked, “Each tree had 56 oranges. If eight slaves pick them equally, then how much would each slave pick?” The other said, “If Frederick got two beatings per day, how many beatings did he get in one week?”

Roach says the principal plans to immediately fill that vacancy. She declined to elaborate further because it is a personnel matter.

Parents expressed concerns about the math problems, and the NAACP and other community acitivists including WAOK talk show host Derrick Boazman called for all of the teachers involved to be fired over the incident.

Officials have said one teacher wrote the questions and the rest of the third-grade teachers used the handout for their classes. It wasn’t clear which teacher resigned.

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