The Misfits. Creekside Chronicles 6

Len and Alex were the first defective kids to escape from their underground orphanage and find a better life on Earth's surface among the tracliodytes at Creekside Meadows. It's a wonderful place to live, and Len wants more orphans to experience life there. On his 13th birthday, Len presents Alex with his idea. He likes it. So does the Creekside Meadow director Lulomen. Shortly thereafter, Len, Alex, their friends Abagail, and Zelda, and led by the resourceful Sendal begin the rescue mission for the boys and girls at the Bentonburg orphanage.
Unknown to them, Jack Tanner, the sadistic director of the Bentonburg boys' orphanage, has stepped up his vicious attacks on young Jules and the rest of the boys who live there. Sendal enlists the help of a small group of rebels to aid in rescuing the poor boys and girls. When one of the rebels' hacks into the orphanage's computer system, she discovers something horrifying. Seeing how much fun Jack Tanner is having punishing the boys, his equally sadistic wife, Marsha Knox, the director of the Bentonburg girls' orphanage, decides to offer her girls for him to torture.
He happily agrees. These are bad people and must be stopped. Len, his friends, and the rebels devise a plan to rescue the poor orphans. They rush to save the kids, but they must avoid patrolling soldiers as well as navigate Bentonburg's streets at night. Meanwhile, Tanner and Knox are out of control and can't wait to administer more pain and horror to both the boys and the girls. Len and his friend hurry as fast as they can, but will they get there in time?