Sometimes I get overwhelmed. I have a large group of girls, some of which complete LOTS of activities on their own, and some who ONLY complete things when they attend. In order to keep track of what everyone has done (completed), I made this Tracking sheet. It's pretty easy. When they have completed one of the requirements, I write what the activity was so that I can try not to repeat it. There is also a space at the bottom to mark off if they have completed the Articles of Faith, written their testimony, and have their interview with the bishop.
The girls still keep track of their individual activities in the back of their book, I just keep one of these papers for each girl in my Activity Day binder so that I can personally keep track of what they have done.
Any questions? Let me know.