Give the kids a five-minute warning that they will need to finish up their game and start to clean. Nobody likes to be abruptly stopped while they are in the middle of something, especially something fun like a game. This will give them a chance to finalize their activity.
Sing a clean-up song, such as this one arranged to the tune of London Bridges:
"It is time to clean the room.
Clean the room.
Clean the room.
It is time to clean the room.
Pick up all the toys."
Encourage the kids to sing along with you. Due to the catchiness of the lyrics, inevitably everyone will start to sing along with you.
Pick up as you begin to sing. Tell the kids to pick up as they sing too. Before you know it, the song will be over and the room will be clean.
Give the kids a five-minute warning before clean-up time is about to begin to ensure a smooth transition.
Assign each child a section of the mess to clean up. The last thing you want to do is create a fight, so make sure that the divided areas are relatively even on the messiness scale.
Decide on a reasonable amount of minutes that the clean-up should take. You can even involve the kids in this decision.
Tell the children how many minutes they have until the room should be mess-free. Make sure that they understand that, in order to win, they need to finish picking up the mess before the timer goes off.
Set the timer to the number of minutes you decided on.
Count to three and start the timer to begin the race. The kids will quickly rush around to beat the clock. This race works well to clean a room quickly.
Give the kids a small privilege if they beat the clock, such as picking out their snack that day.
Give the kids a five-minute warning so they can finish their game and prepare for the tidying-up time.
Bring an empty box, bag or laundry basket into the room where the game or toys are. Tell the kids that it is the garbage truck and that any toys or game pieces it gets will be thrown away or given away to underprivileged children.
Count to three, then start pushing the box along the floor, making garbage truck noises. The kids will rush to pick up their stuff before it gets taken by the garbage collector.
If items get collected by the trash truck, tell them it will go to the dump tomorrow, but give them a chance to win back the items with good behavior until then.