OH I want to do the "Couch Potato" Malia suggested! That sounds like a blast for kids,,,as long as an adult drives.
I have loved the times the youth group did the "Pizza Scavenger Hunt". They arranged, or bought enough uncooked pizza crusts in boxes so each team of about 5 kids could have one. They start with the crust and are given a neighborhood to go door to door asking for pizza toppings. They have a limited time to get toppings, and then have to go to a prearranged member of the church house to bake the pizza. And be back at the youth group hall at a certain time for pictures and judging. I was the prearranged house a couple times and it was fun to see the goofy things they came in with for toppings. I had a lot of fun with them too by not only having the oven heated up waiting, but by handing them a broom to sweep the kitchen, windex and paper towels to wash a couple windows, and a pile of clean laundry to fold while their pizza cooked! The adult who was driving the group was put in the recliner, handed ice water and news paper to relax. It was a real kick to turn the tables on them and make them do chores for a few minutes. Thay really laughed about it. The best thing tho was when they got back to the chruch for the "Judge the Best Pizza" they found real pizzas already cooked and waiting for them so they didnt have to eat the stuff they collected.
The other great group game I like is the "Bigger Better" scavenger hunt. They form teams of about 6 or so. Each team is given a bottle cap. They have to go door to door asking strangers to trade up for a bigger better item. The bottle cap may be traded for a book, and the book gets traded for a shoe, the shoe for a bath towel, then a old kids chair, and pretty soon you may have teams with dressers and big stuff they can barely carry! They all have to get back at a certain time to compare what they have and see who brought back the bigger better item. I actually got a bar stool I loved and gave the group a 6 ft tall old ratty wicker bathroom cabinet I had planned for a garage sale for $3. It was a blast to see them walking down the street all in a row carrying this thing.The family up the street ended up loving the cabinet and used it in their house,,lol,, so, anything goofy that gets them to have fun with no big religous pressure is a sure way to make kids want to come back and see what great fun they can have without drinking and drugs. its always a good start.