Duck, duck, goose? - They all sit in a circle and one person walks around the circle patting each person in the circle on the head saying, "duck", one at a time, until they decide to pat someone on the head and say, "goose". The person "goosed" has to stand up and chase the person who patted them round the circle. If the patter gets round and into their space before the person who patted them catches them then they sit down in the circle and the person patted starts patting.
It is my ds (6) favourite party game.
You can also do a treasure hunt. We did it one year by cutting out paper eggs. Each child had a 10 paper eggs in their colour to find. We had them blu takked to windows, doors, walls, etc all over the house. We did it before the party. They get a sweet when they find all theirs. They can do it in pairs too but it doesn't last so long. Those finished quickly can help the stragglers.
Flour mountain - bit messy - maybe lay out a large plastic table cloth on the floor for this one. On a tray make a mountain of flour in the same way you would make a sandcastle but using a bowl and flour. Then place a sweet on top. Child has to kneel, put hands behind back and take sweet off with teeth. Usually get a face full of flour too - makes for some fun party photos.
Pass the hula hoop. Give each child a straw. They stand in a circle. They put the straw in their mouth and have to pass the hula hoop round the circle from straw to straw. Usually very funny. If the crowd is big you can make two circles.
You can also play the same game passing balloons from between your knees to between the next person's knees with hands behind your back.
Kids also generally love disco dancing - you can give each child a prize eg best jumps, funkiest moves, etc. They all win so all happy. Prize can be sweet or plastic medal or button badge etc.