The 2012 PISA was the first assessment to measure dimensions of social-emotional development. In both the OECD and the United States, about 80 percent of students agreed with the statement “I feel happy at school.” However, while 71 percent of OECD students attended schools where the principals agreed that their teachers foster social-emotional development as much as academic achievement, the United States fell behind at 64 percent. OECD explores methods of supporting such non-academic factors at school.