If you're throwing your daughter a girly, glamorous birthday party, why not make friendship bracelets? Supplies for this project can be as minimal as multicolored embroidery thread; or, you can really glam it up with beads, string, clasps and other doodads. For an extra special touch, pick up a special charm for each girl to string on her bracelet, such as her first name initial.
Unless girls already know how to make this kind of bracelet, it's wise to have someone on hand who can walk them through the different steps. Hobby stores also carry a variety of beading and bracelet kits that should have everything you need, including instructions. Depending on the size of the group, you may want to set a limit on how many bracelets girls can craft to ensure that you don't run out of string or beads before everyone finishes one.
There's a wide variety of friendship bracelets girls can bead and weave with various types of materials. To get an idea of which ones would suit your birthday party the best, check out How to Make Kids' Bracelets.