“Our discipline problems are very low,” Raiche says. “There are no gangs and no violence. Really, sometimes you forget you are working in a Chicago public school.”

Raiche has seen turnover first-hand. This is her third year at an UNO school, and yet she’s one of the veterans. Last year, when she taught at another UNO campus, 75 percent of the teachers were in their first year.

“New teachers are enthusiastic and open to new ideas,” she says.

But in their 20s, teachers are still settling down, and there could be many changes in their lives. That’s happening with Raiche: At the end of the school year, she left UNO to move with her fiancé to Philadelphia.

Christopher Mazzeo, associate director for policy and outreach for the Consortium on Chicago School Research, says that the teacher turnover revealed by Catalyst’s analysis “seems high, and that is worth being concerned about.”

Mazzeo co-authored a study, published in 2009, on teacher turnover in CPS. The study found that 51 percent of elementary school teachers and 54 percent of high school teachers leave their schools within four years. If charter schools are reaching similar rates in just two years, it raises a red flag.