A Gwinnett schools investigation found former Beaver Ridge Elementary School teacher Luis Rivera was the author of a third-grade homework assignment that used slave beatings to teach math concepts.

In a statement to school officials obtained by The Atlanta Journal-Constitution Thursday, Rivera, a teacher at the school since August 2008, apologized and said some of the questions he wrote were in “poor taste.”

Rivera’s 20-question homework assignment used slave beatings and picking cotton to link lessons about ex-slave and abolitionist Frederick Douglass to math computation. One of the problems read: “If Frederick got two beatings per day, how many beatings did he get in one week?”

Rivera told officials he was following the district’s curriculum, which asks that teachers explain what Douglass had to overcome to succeed and become a hero.

Gwinnett County Public Schools officials said the assignment did not undergo a content review before it was distributed to more than 100 students.

“I did not write those questions with the intent of being malicious or offensive,” Rivera said in his statement. “I wrote poorly written questions in an attempt to enhance student achievement. I have brought shame to my family, and my school. For that, I cannot apologize enough.”

Rivera resigned from his $39,170-a-year job on Jan. 13, citing "personal reasons."

According to the Gwinnett schools investigative file, Christina Bartolo was the grade level chair who did not review the homework before it was distributed to students. It was used in four classrooms: Rivera’s, Bartolo’s, and those of teachers Deserae Moore and Maricary Garcia-Carrero.

Five other third-grade teachers did not use the assignment.

Rivera, who has a bachelor's degree from Florida Atlantic University, said that all involved  "immediately felt remorse and embarrassment" when complaints started coming in.

Beaver Ridge teachers are asked to create cross-curricular assignments and assessments and Rivera said he was attempting to do so.

“As a minority myself, I understand the trials and tribulations associated with being a minority,” he wrote. “There was no intent to harm, or to offend. Rather, I was trying to make connections for the students, while completing my assignment of cross-curricular integration.”

The homework assignment also had questions about Mary McLeod Bethune, Susan B. Anthony and Paul Revere.

Bartolo, Moore and Garcia-Carrero received "letters of direction" from school officials ordering them to follow school rules or face disciplinary action, including termination, in the future.

Some parents of Beaver Ridge students who received the assignment asked that counseling be made available for kids.

At a Gwinnett school board business meeting Thursday, Henry White, who does not have children, called the incident an "egregious act of assault on the minds of a kid by an adult" and also recommended counseling.

Beaver Ridge Principal Jose DeJesus is moving quickly to replace Rivera with an educator who has worked as a long-term substitute.