Final answer:
The battles of Lexington and Concord were pivotal as they energized the American war effort, displayed the colonists' ability to challenge the British military, and raised morale and support for the burgeoning revolution.
Step-by-step explanation:
The outcomes of the battles of Lexington and Concord were important to the American war effort because they marked the first armed conflict between colonial militiamen and British troops, setting the stage for the Revolutionary War. Despite being simple farmers and shopkeepers, these militiamen showed they could stand up to the professional British Army. By the time the redcoats reached Boston after these confrontations, their casualties were three times higher than that of the colonists. This boosted the morale of the American fighters and supporters of the rebellion. The news of these events spurred the colonies to action, leading to a rise in revolutionary fervor, and informing the direction of the Second Continental Congress. Moreover, the battles influenced public opinion, including that of key figures like Benjamin Franklin, whose outrage was evident as he accused the British of igniting destruction and violence.