The National Security Language Initiative for Youth (NSLI-Y) program offered by the US Government's Department of State offers merit-based scholarships to US high school students to study particularly needed languages (i.e. Arabic, Mandarin Chinese, Russian, Hindi, Korean, Persian, and Turkish). Applicants who successfully make it through the selection process will be sent abroad for either six-week or one semester long programs. All program related costs (e.g. travel, room, and board) are paid for by the scholarship. More details can be found on their website (link).
(Hat Tip: Government Video)