Classic TV - Tales of Tomorrow - "The Children's Room" (1952)

A couple -- Bill and Rose -- are having increasing difficulties with their son Walt: he talks down to his parents like they are stupid and reads books written in a language that no one understands. The books come from a "children's room" that supposedly does not exist. Once the room is discovered its true meaning is revealed.
https://www.imdb.com/title/tt0717054/plotsummary?ref_=tt_ov_pl

This video is in the Public Domain.