Games for 8-year-old kids include a treasure hunt, a tug of war and a three-legged race. Kids around this age enjoy competitive games and can understand complex rules.
For a treasure hunt, the organizer hides a small bag or box, which is considered the treasure chest. He also places clues around the area. He can have the kids work together on one team, or divide large groups into multiple teams.
In a tug of war, the organizer divides the kids into two evenly-matched teams, and has each team hold one end of a long rope. He then says "go," and the teams try to pull each other a certain distance.
For a three-legged race, the organizer pairs up kids similar in size and ties two of their legs together. They then line up at the starting line and each pair races to the finish.