CNN's Heroes blog profiles Leo McCarthy, a Montana father who launched a scholarship program after his 14-year-old daughter was killed when she was hit by an underage drunk driver. To be eligible, teens have to promise not to drink until they're 21 and to not get into a car driven by someone's who's been drinking. Five years after daughter Mariah's death, McCarthy's nonprofit has awarded more than 140 $1,000 scholarships to high school graduates.
"I wanted to give them encouragement and to tell them that ... you can be better and always be greater in the situation," says McCarthy. Teens who wish to be eligible for Mariah's Challenge must sign the online pledge, be free of any convictions for underage alcohol possession, and submit an application with a 300-word essay. (Read more Leo McCarthy stories.)