How to raise a ton of money?

My friends and I are trying to raise money to go to valley fair. As you all may know it is a fun amusement park located in Minnesota if you don't know what it is here is a link to the website:http://www.valleyfair.com/. Anyways it would be my family which is made up of 4 people my cousin, and at least 2 of my friends. I have already been on vacation to minnesota before and that rounded up about 2000-3000 dollars I think we took 2000 with us but I'm not sure. That was also for The mall of America the Zoo and Valley fair together so.... I was wondering what are some great fundraising ideas like Car washes and selling cookies. If you could think of anything fun and unique tha twould work too. Thank you