The story
From spelling + bee (“get-together, (social) gathering, contest”). The earliest known evidence of the phrase in print first appears c. 1850.
Etymology from Wiktionary, CC BY-SA 4.0.
spelling bee
Today it means: A formal competition in which participants, usually children, are asked to spell out words aloud according to established orthographic conventions, and in which the participants advance by spelling the designated words correctly. Full definition →