INDIANAPOLIS — A teacher arranged a special reward outing with a 15-year-old student as a cover for them to have sex, authorities said.

Sheila Vasquez, 37, Indianapolis was being held on $30,000 bond Wednesday night in Marion County Jail on preliminary felony charges of sexual misconduct with a minor.

Vasquez is a teacher at the Renaissance School, an alternative school for at-risk students in Warren Township on the city’s east side.

Police said Vasquez and the boy, with whom she had been flirting, concocted a plan to have sex while she took him on a lunch outing that would be described to administrators as a reward for recent improvements in his classroom performance.

Police spokesman Sgt. Matthew Mount said Vasquez drove the boy to her home on the north side on May 1 and they had sex.