So a kid brings in some sample comic strips to get a job at the Daily Planet, and Clark (Superman) Kent quickly determines that the art school that encouraged the kid may be perpetrating a scam:

First, Clark calling the kid “no-talent” seems kind of harsh for Superman, even in his disguise as a mild-mannered reporter. Of course, he’s not calling the kid no-talent to his face or anything, but still. And frankly, the art’s not
that bad…clearly Clark hasn’t read some of the black-and-white boom books from the 1980s. Granted, it’s about 20 years too early, but Clark obviously has no idea how good the cartooning world has it.
Anyway, Clark decides to investigate the art school by applying to it himself:

Good gravy, Clark, get it together. …And frankly, I find myself troubled by the idea of a Superman who isn’t super-ambidextrous.
So the art school takes him in, and, via various plot hoohars, finds himself put to work forging famous pieces of art. And because this is a Superman story, Superman travels back in time to learn the skills of the masters directly from the masters themselves. And, on one trip, where exposure to certain energies during his time travel turns Superman younger and, um, blue…well, just check this out:

Imagine if the face on that painting was just left blank. That would have baffled art historians
forever. Or imagine Thomas Gainsborough actually being able to paint a normal-looking face despite having a blue-faced boy as a model, just like he was able to paint a frilly fancy-boy outfit based on a model wearing skintight circus strongman gear.
In the end, the forgery ring with the art school front is caught out and hauled up the river to do a dime in the graybar hotel, and there’s even a happy ending for that kid about whom even Superman basically thought “don’t give up your day job.”

THE UNSEEN IRONIC ENDING: dropping newspaper circulation and shrinking comic pages drive the kid into the more stable and lucrative business of art forgery. OH THE TRAGEDY
from Superman #211 (November 1968) by Frank Robbins, Ross Andru & Mike Esposito