Decorations: Bonnets & aprons for the girls. Bandanas & Cowboy hats for boys.
Food: Beef Stew or Chicken Pot Pie, Biscuits, & Peach Cobbler served on pie tins.
Games: Make & decorate wagons out of boxes and have a relay race. Sing pioneer songs. Make up campfire stories. Play children's games such as hopscotch, jump rope, tag, marbles, etc..
Here is one game I found on the internet:
Drop the Handkerchief is similar to Duck-Duck-Goose. Form a circle of players facing each other. The person that is "it" will go around on the outside of the circle and drop a handkerchief behind one of the other players. Then he/she has to race around the circle in hopes they won't get caught by the person the handkerchief was dropped behind. The person where the handkerchief was dropped picks up the handkerchief and chases after the person. The first one to sit in the empty spot wins. The one who loses will be "it" next.