Learn in the sense of “teach” dates from the 13th century and was standard until at least the early 19th.
made them drunk with true Hollands—and then learned them the art of making bargains — Washington Irving
But by Mark Twain’s time it was receding to a speech form associated chiefly with the less educated.
never done nothing for three months but set in his back yard and learn that frog to jump — Mark Twain
The present-day status of learn has not risen. This use persists in speech, but in writing it appears mainly in the representation of such speech or its deliberate imitation for effect.
Some languages use the same verb for learning and teaching. People that have those languages as primary language will often use learn in place of teach when producing English.
From Merriam-Webster:
Learn in the sense of “teach” dates from the 13th century and was standard until at least the early 19th.
But by Mark Twain’s time it was receding to a speech form associated chiefly with the less educated.
The present-day status of learn has not risen. This use persists in speech, but in writing it appears mainly in the representation of such speech or its deliberate imitation for effect.
Some languages use the same verb for learning and teaching. People that have those languages as primary language will often use learn in place of teach when producing English.