Reducing class size is one of most effective ways to improve student achievement. But CPS refuses to even address the issue and, thanks to school closings, student-based budgeting and other wrong-headed policies, class size is ballooning across the district. P4T analyzed class size data from Fall, 2014, the most recent data available and found that nearly one-third of CPS's youngest students attend classes in excess of guidelines on class size. Read the report here.