Many teen dramas follow the exploits of sports teams, so these scenes are baked into the shows' DNA. If we aren't following the jock's journey, then it's imperative to see our non-jocks being awful at sports.
Again, Freaks and Geeks set the standard for this approach with their dodgeball scene. If you just can't shoehorn in a gym class moment, then settle for watching the characters run through a park (Gossip Girl) or sailing (The O.C.). But without a gym scene, there's no awkward locker room interaction, and without an awkward locker room scene, then it all just feels meaningless.