Wheel barrow: Pair off in twos - if lots of Mums, Dads, older siblings attending then one oldie + one child.
Larger holds legs and the smaller walks on arms. Set out a finish line (or just have someone stand at either side of the notional finish line and shout GO!
Then enjoy!
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best if a warm day
Pass the water balloon.
Fill ordinary balloons very full of water. Store in washing up bowl or bucket.
Have a group of children (5 or 6 works well) line up in teams. Set the water balloon on the ground. Last person runs to front and places water balloon under chin of first person. Last person runs back to position whilst first person carefully passes water balloon under the chin of second person. Second person passes to 3rd person, 3rd person passes to fourth person and fourth to fifth. When the fifth person has it - he has to run past the 1st person to win for his/ her team.
Winner is first one back.
Anyone who bursts the balloon is disqualified.
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Chinese whispers.
Sit in circle. First person tells person next to them a word - goes all the way around the circle back to first person who confirms whether the word was correct or not.
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DUCK DUCK GOOSE
Sit in big circle. Someone is chosen to go first.
They walk around the circle tapping three heads.
First head: say duck
Second head: say duck
Third head: Say goose & then run like mad. The first person has to go around the circle to the open place and sit down without being caught by the GOOSE.
If he is caught by the GOOSE - he's got to go again.
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Dodge Ball:
Big circle.
Two ways to play.
Start with half in circle and half outside - so the ball throwing is very fast and furious (ideal for Y3 upwards). Or for younger children - start with one or two outside and everyone else inside.
Nice play way: Use a light plastic ball (you know the kind you get at supermarkets with characters) & have it that the ball has to bounce before hitting anyone.
Not so nice play way: Just throw the ball at people.
This can get very wild indeed - so judge the character of the kids at the party and whether this is worth doing. Can be a lot of fun - but can also be upsetting and a bit rough if out of control.
HTH