I do not really see vouchers affecting the small schools unless that school is close to a private school. In the area I am in for most of the 1A-3A schools they are at least an hour away from a private school. I know the parents in my school district are not going to drive an hour for their child to go to school.

The thing that could affect small schools is homeschooling. Vouchers can be used for homeschooling. I don't really think it will be a factor but that is what will affect the small schools in rural areas.