Basic Trope: An activity is treated as though it had much more importance than most people in Real Life give it.
Straight: In the year 202X, hopscotch has become a major league sport. Millions of people watch hopscotch games live or on Three-V, the best hopscotch players make excellent money, and kids want to grow up to be just like their favorite "scotchers". The main characters of the story all either play hopscotch, or are the close friends and relatives of those that do. Other games and activities are mentioned from time to time (Katie was a champion ropeskipper before crosstraining into hopscotch), and Ken can be seen in regular boring classes every so often between matches.
In the second season, hopscotch has become the only sport on Earth. Top scotchers are worshipped like rock superstars in our world, Ken and Katie attend a special school that teaches hopscotch (and apparently nothing but), every player has named special techniques, and there's an Ancient Conspiracy out to rule the world by taking over the hopscotch league. Characters who don't play hopscotch are reduced to Combat Commentator or Damsel in Distress roles.
Multiple world wars have been started over hopscotch.
Downplayed: Ken and his teammates/rivals take hopscotch seriously, but the rest of society just thinks of it as a game, and not a particularly important one.
In order to be the best at a particular sport or activity, you have to treat it with seriousness, even if it seems silly to outsiders to do so.
Due to a whim of an ancient god, hopscotch gives untold mystical powers to those who can master it.
The universe works based on the focus of people. Hopscotch happened to become all powerful because so many people played it as kids they remembered it well, causing good things to happen when it's played.
Inverted: Normally serious things, like war or disease, are treated as though they're no more important than children's card games.
Subverted: In the middle of a tense hopscotch match, Ken stops and says, "Dude! We're taking this all way too seriously! It's just a game, we should relax and have fun".
But then Team Evil reveals that Katie's been poisoned, and the only way they'll give Ken the antidote is if he wins the match.
Katie refuses, claiming "This stopped being a game the moment we started hopping".
While the hopscotch players are engaged in their fierce battles, we cut to ordinary people getting on with their ordinary days, completely uninterested in the proceedings. When one side loses, it has no effect on the larger world.
Both sides of a major war, who have been bitter enemies for generations, halt their aggressions mid-battle when a corporal comes running out into the battlefield yelling that he has the results of the Hopscotch World Championship.
Zig Zagged: Most of the episodes concentrate on the fierce hopscotch battles for the fate of humanity, but we also see the characters taking days off to do other things that are important too, or just playing hopscotch for fun.
While all the characters enjoy their favorite activities or sports, no one gets carried away with it.
Enforced: "Is there anything we haven't made a sports anime out of yet?" "Ummm...hopscotch?"
Lampshaded: "You know, I bet that no one back in the 2010s would have believed that hopscotch would ever get so big". — "You mean other than Konami?"
Invoked: Ken decides to become the best hopscotch player 'ever, no matter what.
Exploited: While the world obsesses over hopscotch, Kim gets away with using a ton of underhanded tricks to make money through a trivial, unimportant institution: the stock market.
Defied: "Oh for God's sake, it's just a children's hopping game. I'm not going to let it take over my life".
Discussed: "You know Bob Bigbux lost all his money betting on pro hopscotch? Me too".
Conversed: "Anime can make anything look awesome and important, even hopscotch".
Deconstructed: Ken and Katie suffer all the normal effects of concentrating on one activity to the neglect of all others. Their school grades suck, they have no normal relationships with outsiders, and they start taking performance-enhancing drugs with all the side effects those have.
Reconstructed: "Quintuple Square Hop Inversion!" Damn, that's cool.
Played For Laughs: The view on the game is split. Those who take it seriously, and those who don't get what the fuss is all about. You see one side who many glows and explosions before they start skipping, and then you see normal people watching other hop around, occasionally preforming a gymnastic feat.