This game is a favorite of kids but has the potential to get quite messy so it might be a good idea to play towards the end of your party and only play this game outdoors.
Break the kids up into teams of two players. Outside, position the kid in two straight lines so that each player is facing their teammate. Give all of the players on one side an uncooked egg. Countdown One, Two, Three, Toss! and the kid with the egg must toss their raw egg to their teammate across from them. The teammate tries to catch the egg without the egg breaking. If the egg breaks for any reason that team is eliminated.
Once the turn is complete all remaining teams should take one step away from each other and the player with the egg tosses it back to their teammate. Repeat the tossing and stepping apart in turn until only one team still has their unbroken egg. Congratulations, you have a winner.