Rope off areas for different activities like an arcade section. Most any arcade style game will do well in this area. Another area can be for tossing rings on bottles. Blow up balloons and tape them to a corkboard for darts. Several boxes taped together to create a tunnel or maze.
Some brave parents can even buy goldfish for a ring toss in a goldfish bowl.
Have about a dozen small fish bowls setup with water but only a few will have a real goldfish in it. Have popped popcorn handy with small popcorn bags they can spend tickets on to buy. Another refrigerator box works well as a popcorn stand.