Rambunctious describes someone or something showing uncontrolled exuberance.

// On my first day of student teaching, I was tasked with managing a class of rambunctious youngsters.

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"To juvenile loggerhead sea turtles, a tasty squid might as well be a disco ball. When they sense food—or even think some might be nearby—these reptiles break into an excited dance. ... Researchers recently used this distinctive behavior to test whether loggerheads could identify the specific magnetic field signatures of places where they had eaten in the past. The results, published in Nature, reveal that these rambunctious reptiles dance when they encounter magnetic conditions they associate with food." — Jack Tamisiea, Scientific American, 12 Feb. 2025

Rambunctious first appeared in print in the early half of the 19th century, at a time when the fast-growing United States was forging its identity and indulging in a fashion for colorful new coinages suggestive of the young nation's optimism and exuberance. Rip-roaring, scalawag, scrumptious, hornswoggle, and skedaddle are other examples of the lively language of that era. Did Americans alter the largely British rumbustious because it sounded, well, British? That could be. Rumbustious, which first appeared in Britain in the late 1700s just after the signing of the Declaration of Independence, was probably based on robustious, a much older adjective meaning both "robust" and "boisterous."