Hey hon. I know you may have seen this already, but here is the link to that cool calendar that tells what your little grand kitties should be doing and at what age. It really helped me out when I was wondering about their eyes. I hope that helps http://www.purrinlot.com/kittenbirthcalendar.htm
It will eventually fall off... ripping it off could cause problems.... you could accidentally rip the tender skin at the base. You could cut it about an inch from the base if you are sure all the tissue is dead. Some of mine didn't fall off until later, so I wouldn't worry about it.