What's a good photography project for my sister (who's almost 10) and I to try?

I have a camera. An old camera, a not very good camera, but hey. It works. Anyways, I like photography. I’ve tried a few times at these “photo a day” projects (that are supposed to last a year but I’ve only done a month long). I’ve been thinking for a while that my sister and I should try something together. I was thinking we could take a different kind of a picture of us together each day for a month. Any other ideas? Does anybody have any stories about projects they’ve done? Also, I want some ideas and pictures to give my sister an idea of what I want to do. If you’ve done something like this before, and have pictures online, could you give me a link? Or do you know of any projects online?

P.S. Oh by the way, it’s a digital camera that I have. I forgot to say that and now I didn’t want to go back and find a good place to stick it in. ;)