Here, speed and balance go hand in hand to create an action-packed marble relay. Players: 4 or more
To get started: Cut the cardboard tubes into equal-length troughs, one for each player (ours were approximately 1 foot long). Have players line up 2 to 3 feet apart.
To play: The first person in line sets the marble on one end of his trough, then, without touching the marble, rolls it the length of his tube and into the next player's (it's okay if troughs touch). That player passes the marble to the next, and so on. As each player passes the marble, he moves to the end of the line, eventually catching the marble again and passing it on. If someone drops the marble, he's out and the marble goes back to the beginning of the line. Whoever's left is the winner.
Our testers' twist: For larger groups, divide the players into 2 teams. Give each team a marble and have them race to pass it around the group 3 times. If a team drops their marble, they must start all over again.