Have You Considered Majoring in ‘Overwatch’?

It’s a scene unfolding at thousands of “cram schools” across South Korea: A dozen kids huddle in a fluorescent-lit classroom, staring mutely as an instructor drones on. Except at these particular academies, luminous displays and tricked-out headphones stand in for textbooks and highlighters. Also, the teacher is a millennial hipster who imparts wisdom such as “Don’t expect to pass under this bridge without a fight.” Shouts and high-fives erupt sporadically.

That’s because these teens aren’t cramming for college—they’re gunning to become esports champions. Professional video gaming began in South Korea more than a decade ago, giving rise to leagues that now pack stadiums and draw hundreds of thousands of eyeballs to Twitch livestreams for tournaments. With esports maturing into a $13 billion global concern in which heavyweights from Activision Blizzard Inc. to Amazon.com Inc. and Tencent Holdings Ltd. are setting up leagues and securing streaming rights, kids as young as 12 are enrolling at academies popping up around Seoul. These schools exist for one purpose: grooming virtual death dealers for the rigors of esports’ noon-to-2 a.m. grind.