Criss cross applesauce is a phrase used in American classrooms to tell children to sit with their legs crossed, while yeet is internet slang for throwing something or moving suddenly with excitement. Combining the two turns a gentle instruction into an absurd punchline, which fits the style of short meme sounds shared on soundboards and social video apps. The clip is not tied to a single film, show, or viral video, so creators use it flexibly as a reaction or transition. Its appeal comes from that contrast: a wholesome setup followed by a loud, modern payoff.