The Bolo bat was a child's toy

Toy

A toy is any object that can be used for play. Toys are associated commonly with children and pets. Playing with toys is often thought to be an enjoyable means of training the young for life in human society. Different materials are used to make toys enjoyable and cuddly to both young and old...

 popular in the 1930s through the 1960s. It consisted of a round wooden paddle-like bat with a handle, not unlike a ping-pong paddle, attached to the center of which was a piece of elastic band about three feet long. Attached to end of the elastic band was a rubber ball about an inch in diameter

Diameter

In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circle. The diameters are the longest chords of the circle...

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The child would bat the ball as far as the elastic would allow it to travel. When it reached the furthest distance from the bat that the elastic would allow, it sprang back at the bat where it was hit again and again. The object of the game was to see how many times the child could hit the ball and have it return and be hit again. Children competed against themselves and others for the greatest number of successful hits.

This is possibly the same thing as a paddle ball

Paddle ball

Paddle ball is a one-person game played with an attached ball and paddle. Using a flat paddle with a small rubber ball attached at the center via an elastic string, the player tries to hit the ball with the paddle in succession as many times as possible. The paddle is usually made from either...

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