The Mensa Foundation and New Mexico Mensa offer scholarships to students who will be enrolled in post-secondary education for the 2015-2016 school year. Awards range from $300 to $4000 ($1000 renewable for four years). The only requirement is an essay of not more than 550 words explaining your goals and how your education will help you reach them. The entire process occurs on-line.
For a complete set of rules, see http://www.mensafoundation.org/scholarships.