McKinsey used machine learning to discover the best way to teach science

There is a long-standing, red-hot debate in educational circles about the most effective way to teach kids. Others advocate for inquiry-based learning--where students drive their own learning (pdf) through discovery and exploration, working with peers and developing their own ideas--arguing it results in deeper, and more meaningful learning. The two are sometimes pitted against each other as "sage on a stage" (teacher directed) vs. "guide on the side" (student-led, or inquiry based). Both cite ample evidence to prove the superiority of their method (see here for teacher-directed, and here for inquiry-based). McKinsey applied machine learning to the world's largest student database to try and come up with a more scientific answer.