I think regular (day time) noise levels are perfectly fine outside until at least 9:00 and really more likely 10:00. If it gets later than that I can see asking them to please keep the volume level down. I would actually as the KIDS first. It does not sound like they are doing anything wrong--no need to go to the parents =--just ask nicely if they would mind keeping it down after 10 so you can get some sleep.
Your DD will probably get used to the noise quickly and then be able to sleep through it.
As far as what is too late on a school night

that varies from kid to kid. Some kids need more sleep than others. Some have to get up earlier than others for school. Some are homeschooled and can sleep in if needed/wanted. I doubt many 14 year olds are asleep before 10 or 11. I think being out playing with friends is much better than inside watching TV or playing on a computer.