13th Birthday (Party Ideas!)

Hiya!
In 4 months I will be turning 13 years old. Now, because I am gonna become a teenager I want to do something special to celebrate. Last year I went bowling with a bunch of friends, and this year I wanna have some king of activities day.
My party will start at about 10:00am or 11:00am and not finish until about 9:00pm.
However I would like about 1-2 people to sleepover.
But what can I do to keep people amused for the other 10 hours!?
Please can someone help!
Here are some extra details before you come up with an idea!
1) My B-Day is in Autumn, so it may be raining and will be cold.
2) I don`t have that much money to spend on a party
3) I don`t want to go swimming (because I go to much!)
4) I don`t live in America were you can just go and book in at the nearest hotel.
5) I probably can`t get a limo because my other friends have already done that and they also cost to much!
I wouldn`t be surprised if you can`t come up with an idea because I am very fussy and have made it awkward for you! Good Luck x