Yes, there is a mercy rule in high school football in many U.S. states. The mercy rule generally triggers a continuous running clock once one team achieves a large lead—typically around 30 to 42 points—to reduce game time and prevent further humiliation for the losing team. This rule usually takes effect in the second half of the game, with the clock stopping only for specific events like timeouts, injuries, or scores. The exact point differential and timing when the rule applies vary by state and league, and some states may end the game early if the lead is large enough. Not all high school leagues have the mercy rule, and its application can differ widely.