My granddaughter is also 10, and she loves the
www.barbie.com site. If she likes crafts, you might like to check out crayola.com. And for your own interests, and some free coloring pages, check out igrandparents.com. You can also go to google.com and type in "free coloring pages." Some of the pages are interactive and can be colored right on the monitor, but most of them require a printer.
We went into a site called
www.lilbowwow.com, or something similar to that, for one of the young rap stars...and unfortunately when we did that, we ended up with a bunch of porno pop-ups...so just be aware that this can happen, and monitor your DGD's usage of the internet. These pop-ups hit us so hard and so fast that day that I couldn't click out of them, my DGD was totally freaked, and I ended up having to shut down manually...which as you know can be a pain in the tush.
Good luck, and have fun with your DGD. Ten is such an interesting age....they're just sooooo busy, lol.