The Brazoria County NAACP is among the groups demanding that the students be disciplined.
"How is that child able to even make it on campus? That's just utterly ridiculous and unacceptable," Brazoria County NAACP President Eugene Howard said.
In a joint release with the Smart Scholars Foundation, the NAACP said the students showed up Friday dressed in Confederate attire, which would violate the district's dress code.
WATCH: NAACP holds press conference on students wearing Confederate flag gear.
The groups shared a screenshot of a photo showing three students, one of them wearing a sleeveless Confederate flag shirt.
Hopefully, we can bring ourselves together," Pearland ISD parent, Harvey Wolff said. "Get a good conclusion. A good closure to this, and hopefully, the school district will reply properly instead of what we've received so far.
Pearland ISD released a statement explaining that the high school administration was "made aware of students in violation of the district dress code that was clearly unacceptable. PHS administration has addressed this situation. Per the Pearland ISD dress code, apparel or accessories which include cultural divisiveness and racial intolerance may not be worn. Appropriate disciplinary action has taken place in accordance with the Student Code of Conduct."
"We want to be clear that all students, faculty and staff are welcome at Pearland ISD. We teach and model tolerance for all, and the diverse community of Pearland promotes a level of inclusiveness for which we are proud," the rest of the statement continued.
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