Despite your top-notch plans, child’s play can head south—fast. Just one toy that both kids must have at the same time and, well, game over.

Don’t spill the beans
Attach sturdy paper plates to the tops of plastic headbands with Velcro (use the two-sided, self-adhesive Velcro tape found in craft stores, and adhere one side of the tape to the band and the other to the plate). Have kids put the plate-bands on their heads and get ready to race. Spill a handful of dried beans onto each plate. Whoever gets to the finish line with the most beans left on the plate wins.

Island hopping
Spread a few Hula Hoops around the backyard or family room and tell the kids they’re islands; the lawn or floor is the water. Play music and have the kids pretend to swim from island to island. When the music stops, kids have to get to the nearest island—only one kid on each island. Keep going until the players are pooped.

Bouncing off the walls
Choose a room that’s free of fragile, breakable items. Gather a bunch of different-sized balls: Ping-Pong, tennis, small rubber balls and such. Place a laundry basket and a large, unbreakable mixing bowl a few inches from a blank wall. Have the kids bounce the various balls off the wall to get them into either container. Silly scavenger hunt Get the giggles going on this outdoor trek by creating find-it lists that will make your hunters—depending on whether they’re boys, girls or both—laugh and use their creativity. Example: two gross bugs, one beautiful flower, three magic stones, one piece of lost treasure, two mud pies. What to Do If...

Meltdowns, tantrums, shyness, shattered vases: They can be challenging, even embarrassing, but they’re normal. “Most parents are too worried about what other parents will think about their children, but all children struggle with sharing and impulse control and learning not to hit or bite,” says Dr. Jenn Berman. “Kids are supposed to misbehave. That’s their job.”

Your job: Apologize. If your son misbehaves or breaks something, apologize to the child or his parent or both. But if a visiting child misbehaves, it’s not a good idea to give him a time-out. Discipline should be reserved for the child’s parent. You can say something simple such as “We have a house rule against hitting.”

Practice prevention. If either your child or his friend is getting tired or unruly, you can remove yours from the situation or, better yet, create a diversion. For the most part, let the kids work out their own problems. If something does happen, most parents have empathy. And they’re probably relieved if their kid wasn’t the perp.

Help your child share. Before your guest arrives, let your child put away two or three toys he just doesn’t want to share. Explain that everything else is fair game.