Several countries have recently begun large-scale educational interventions to respond to low learning outcomes. The evidence used to justify national or largescale programs typically has emanated from pilot initiatives that increasingly have provided rigorous evidence of impact on learning outcomes. For example, several recent meta-analyses showed a dramatic increase in results from pilot programs focused on improving learning outcomes while also using rigorous research designs (Conn 2017; McEwan 2015; Murnane and Willett 2011).
