For my daughter's 9th birthday in May, we sent an invitation to all her friends with a photo of an old drive-in. On the inside of the invitation we had clip art of all the old movie candy, popcorn, soda, etc. The kid's came to the house, at 6pm (It was still light out). The kids all got a beach towel and we played games, like musical towels and catch the towel. Then the kids all put there towels out by the projecter and screen. that was set up outside. When they found their places on the grass, they then came to the concession stand" which was our kitchen window. We had a big sign on the outside with all the food that the kids could order. When the kids came to the party they were each given some play money (in purses and wallets) so once they ordered their food (popcorn chicken hot dogs chips carrots) they had to pay for their food with the money (it was also to be used later for the popcorn and candy).  Once they got their sweets and popcorn the the movie started and they all ate their food while they watched their movie.  We had an intermission and played flashlight tag.  The kids also each got glow sticks that they could wear.  All in all they kids had a blast!!! And so did the parents!"