My 13th I had a friend stay over & all we got was pizza!
Get a couple of girly DVD's & ask if they'd be into make overs or doing their nails or something.
Clueless is a few years old now, but I reckon it's still a cool movie. Ummm...Mean Girls is another one. My Boss's Daughter with Ashton Kutcher & Tara Reid in it is hilarious, but it is M rated. I think it'd be OK, but maybe you should watch it first to make sure you approve. There are heaps of others anyway!
Have fun!!
They could have a pinyata or pin the tail on the donkey when all the girls are there. Immature I know, but fun!