Khula is the right of a woman to ask her husband for a divorce and to offer him a compensation in case he does so. Following the Sharia the husband has no right to ask for a compensation of a higher value than that what he gave his wife when they married.
After divorce the former husband is responsible for education, food and residence of children. The children live with the mother for 7 years. After 7 years children have the right to live with father or mother, as they decide.