My sons are 8 and 6 (almost 7), they go to bed between 8.30 and 9pm depending on how tired they are that night. At the weekend I let them stay up until normally around midnight as they get as long as they want to lie in in the mornings as long as we don't have anything on. If they are tired thought they will just take themselves upstairs and fall asleep, normally watching a DVD lol x