A week after the mass shooting at a Texas school, three teens threw a scare into the Jersey City school district when they tossed lit firecrackers into an open school window, district officials confirmed. No one was injured in the June 1 incident at School 8 on Franklin Street in the Heights because students were in the lunchroom and the classroom was empty, schools Interim Superintendent Norma Fernandez told The Jersey Journal. Jersey City spokeswoman Kimberly Wallace-Scalcione said the three boys, a 13-year-old and two 15-year-olds, were taken into custody a short time later, just before noo…