The Clark County, Nevada, school district, said it is aware of an "isolated incident" in which a substitute teacher taped a 9-year-old boy's mask to his face after he removed it. In a statement, the school district said that it is "dealing with the employee through the proper channels." The boy's mother, who wasn't identified by the media, said the boy got a drink of water and forgot to put his mask back on. "The teacher did not tell him to put it back on or send him to the office," she said. "She instead pulled him up in front of the classroom in front of all of the students and she then taped the mask across the top of his face."