An administrator at a Manhattan high school admitted to having sex with four female students, according to a report by the New York City Department of Investigation.

The administrator, Malik Taylor, 31, had sexual intercourse with students who ranged in age from 16 to 19, and also sexually harassed four other students while he worked as a community assistant and a dean at the high school, the Business of Sports School in Midtown, according to a report by the special commissioner of investigation for the city’s schools.

In an interview with investigators in June, Mr. Taylor admitted that he had had unprotected sex with students in motel rooms, in the back of his car and in classrooms after school. He made lewd comments about the size of students’ buttocks and breasts, and sent inappropriate text messages from a cellphone assigned to his wife, the report stated. He also asked one of the students to buy marijuana for him, it said.

Mr. Taylor e-mailed his resignation to the school’s principal, Dr. Joshua Solomon, in May, after one of the students told him that she had reported him. That student told a teacher that she was having a sexual relationship with Mr. Taylor, and that she knew of others who were as well. The teacher then told the school’s assistant principal, Rosa Choi, who notified the special commissioner’s office.