Children of the Corn: The Gathering (1996)

All the kids in a town over night become feverish and have convulsions. The next day they start to become evil, change their names for those of kids killed long ago, and then start killing any adult in their path, in vicious and mysterious forms. A young woman who has just returned to town tries to find out what is happening, while trying to protect her transformed young sister. However, the kids are starting to revive their leader...