Ericka Mingo’s older son has done well at Chicago Virtual and is due to graduate this spring, doing his part to boost the school’s four-year graduation rate, which last year fell to 44%, one of the lowest in CPS. The rate of students who graduate after five years of high school at Chicago Virtual is 70%. Mingo’s younger son started at Chicago Virtual as a kindergartner, but she said she pulled him out during third grade after she saw drastic changes in the school.