Not that I know of on the iPods and iPhones themselves, but if you go to your modem's webpage (usually accessible by entering this into the address bar: 192.168.1.1), there may be settings to restrict connection between those times, or you could simply turn the modem off!
Some ISP's allow time restrictions, I use TalkTalk and my parents block me from using certain websites (e.g. Facebook) at certain times
Why don't you ban them from taking their iPods/iPhones upstairs at night and keep them with you.
thanks for the quick replay.
I've already checked my modem's setup page with no luck, ( it's a 7 years old modem, lol).
I can't turn off the wifi becuse i use it during these hours my self sometimes.
I could've ban them from taking there devices with them but i wanted to check and see if there is a better way to solve this little problem.