Maybe she'd like one by using a distant crumbling castle.
If truly to extend the party, opt for pizza lunch or dinner, or may take all of the teens out for Chinese, tacos, or whatever the birthday teen desires. http://www.silverbardgames.com/wiki/doku.php/gizli_bulusmala_ve_kisisel_ve_ile_in_ko_unmas%C4%B1