Yes there are, though they're not really identifiable as sequels, but they do take place in the same world.
THE GIVER At the age of twelve, Jonas, a young boy from a seemingly utopian, futuristic world, is singled out to receive special training from The Giver, who alone holds the memories of the true joys and pain of life.
GATHERING BLUE In this speculation on the nature of the future of human society, life in Kira's community is nasty, brutish, and, for the ill or disabled, short.
MESSENGER In this novel that unites characters from "The Giver" and "Gathering Blue," Matty, a young member of a utopian community that values honesty, conceals an emerging healing power that he cannot explain or understand
They're all really good books, and you can sort of see it all come together at the end.
Enjoy