No Child Left Behind has been on the books now for four years and the jury is still mixed on its success. A new study released this week by the non-profit independent group “Center on Education Policy” finds that NCLB, as it’s known, is having a significant impact on students and educators. On the one hand, schools are more effectively using test data to adjust teaching. At the same time, though, they’re reducing instructional time in other subjects to make more time for reading and math. WBHM’s Tanya Ott spoke with the Jack Jennings, president of the Center on Education Policy.