There are several reasons that some Christians don't like Halloween. For many it's because of the roots of the celebration, others don't like the scare factor. Christian and non-Christians alike worry about the candy that's given to their children by total strangers. Many churches now offer an alternative to Halloween and host a Harvest Festival on October 31st. Children dress in non-scary costumes and decorations consist of pumpkins, hay and corn stalks. There could also be a petting zoo or hay rides offered, as well as plenty of games.
Simple carnival-type games are a lot of fun at a harvest festival and can be inexpensive to make. Orange traffic cones work nicely as a target for ring toss, and the color fits in with the theme. A giant cardboard pumpkin with a holes cut out works for bean bag toss. In warmer areas, consider holding a water balloon catch, where the last pair of children with their balloon still intact wins. Bobbing for apples is another kid favorite. Older children can participate in a pumpkin "carving" contest, while the younger ones can be involved in a pumpkin "drawing" contest. Hula hoop competitions can also be a lot of fun at a harvest festival. Don't forget to award prizes for the most original, the best Biblical character, cutest animal and least scary costumes.
Lambs, ducks, donkeys, oxen and turkeys are animals that many people associate with autumn, so frequently churches like to include animal games in their harvest festivals. Play follow the leader with a very large group, making animal movements. The same thing can be done with Simon Says, for instance, "Simon says 'gobble like a turkey.'" Pin the tail on the donkey is a well-known animal game. Animal relay races, where the children need to move like a different animal at each stage of the race, can be a big hit.
Trunk or Treat offers a safer version of Trick or Treat. Adults stand in the parking lot near their cars with the trunks open. The kids yell "trunk or treat!" when they arrive at each car trunk and receive candy. Candy can also be used in relay races--instead of the egg-on-a-spoon race, try balancing a candy pumpkin. Hold a candy hunt that's similar to an Easter egg hunt, hide well-wrapped pieces of fall-themed candy in a designated area, then let the kids go wild. Inexpensive items like decorative pencils or small toys can replace some of the candy.