Brooke Harris was dismissed in March from Pontiac Academy for Excellence after she supported students' efforts to plan a wear-a-hoodie-to-school day. Martin was wearing a hoodie on Feb. 26 when he was shot to death by a neighborhood watch volunteer.
A number of groups, including the Southern Poverty Law Center in Montgomery, Ala., have called for Harris to be reinstated.
"I'm really confused why I got fired," Harris told The Associated Press. "I don't think I did anything wrong."
According to the SPLC, a national civil rights group, Harris' eighth-grade journalism students asked her about the death of Martin, 17, who was unarmed when he was shot in Sanford, Fla. No charges have been filed.
Harris gave the students an editorial-writing assignment on the shooting. But the students wanted to raise money for Martin's family and asked the school's administrators if they could each pay $1 to wear hoodies instead of school uniforms for a day, the group said. It said the school regularly has fundraisers in which students are allowed to "dress down."
The literature teacher said she approached school administrators "through the chain of command" but that superintendent Jacqueline Cassell said the project could not go forward. Harris said she was in the process of explaining this decision to the students when she was called for a meeting with Cassell.
The superintendent suspended Harris for encouraging the students and then fired her after she showed up at the school to drop off prizes for students when she had been told to stay away, the SPLC said.
"I didn't tell the kids, 'Let's go and do it anyway.'" Harris said. "I was actually, literally, in the process of talking to my kids about what we could do instead when (Cassell) requested the meeting with me and told me that I needed to let it go."
Cassell said she couldn't discuss personnel matters, but that she wanted students to focus on learning, not activism.
"I'm a child of the civil rights movement," Cassell said. But "this is not the time in the school year" to distract students from academics.
"In every situation, there are work rules," she said. "When rules are violated, there are consequences."
Harris said her teaching record was clean and that Cassell "wouldn't let me defend myself."
Dawud Walid, executive director of the Michigan chapter of the Council on American-Islamic Relations, said the Academy's decision was a "travesty" that would only hurt students.
"It taught the students who tried to organize and tried to raise their voice in terms of social justice that they will be repressed," Walid said at a news conference at a Detroit church. "Instead of empowering our children ... the Pontiac Academy is actually teaching children to internalize oppression and internalize racism."
A rally about the Martin case and Harris' firing was scheduled at the church - King Solomon Missionary Baptist - for Tuesday evening. Harris was expected to be there.
Harris said she still wants someone from the school to provide more details on why she was fired.
"I just want a reason," Harris said. "She's got my phone number, and I'd appreciate if she'd tell me what I did wrong."
