We tested dozens of games with three sets of kids, looking for those that were rowdy enough for kids to love but friendly enough that nobody would feel like a loser.

We had three criteria:

Activity. In this increasingly sedentary world, kids need motion and sometimes a little commotion.

Flexibility. We wanted games that worked with a range of ages and with four kids or ten.

Enjoyability. They had to be games that kids will keep playing by themselves, simply because they are fun.

1. Shark!

Put hula hoops or beach towels on the ground to serve as dens for all the "fish." One child gets to be the shark. When the shark calls, "Fishie, fishie, cross my ocean," the fish have to move to a different den. If, while out of a den, the shark tags them, they get to be sharks as well. The last remaining fish becomes the first shark next time. Adults can also remove dens, forcing kids to stand together on one.

Tip: For extra fun, the shark can tickle the fish.

Variations: The shark can be a T. rex, and the fish can be vegetarian brachiosaurs. Bird lovers can be hawks and mice. Construction buffs can be loaders and boulders, and so on.

Optimal age: 3 and up

Number of players: 4 or more

A parent observes: "There's nothing like a shark-empowered 4-year-old to keep three big kids huddled in a hula hoop."

2. Mouse Tails

Tuck pieces of string or yarn about a foot long into the backs of the kids' shoes. After you shout "Go!," the kids try to step on each other's tails. When all the tails are lost, replace and repeat.

Tip: Have extra string on hand.

Variations: Tuck white socks into waistbands for Bunny Tails, which other players grab.

Optimal age: 2 and up

Number of players: 3 or more

A parent observes: "My daughter had as much fun braiding the tails as playing the game."

3. Blob Tag

The youngest child gets to be the first "it." (They usually consider this a privilege.) When he or she tags someone, they join hands and have to tag another, on and on, until everyone is holding hands.

Tip: Keep the play area small. Kids 5 and under have a hard time catching each other.

Variations: Tunnel Tag — When tagged, you freeze and someone has to crawl between your legs to free you. Shadow Tag — When "it" steps on your shadow, you become "it."

Optimal age: 2 and up

Number of players: 4 or more

A parent observes: "My 2-year-old had no idea what the rules were, but he had a great time chasing everybody."

Originally published in Wondertime magazine.