Ideas for a girls 14th birthday party in spring ?

my birthday is in early spring , ( april 4th ) but i always think about it early ! because i always want to have a great party ! so , i want to do something big with just a 2 - 5 friends , so it can be expensive , but what should i do ? any ideas ? ( i live in pennsylvania about a half hour outside of philly ) thanks for any ideas ! everything helps ! <3