I can't believe the parents who put their 6 yo's to bed on a weekend at 8pm. My daughter would think I had 2 heads if I told her to go to bed that early. Plus with all the running around we do during the week, weekends are time spent with family and that also includes Friday nights.
To OP: DD , who is 6yo, BTW, was invlited to the kind of party you are having about a month ago and is invited to another one next Friday. Great idea, IMOP!