They are the latest craze - water yo-yos.
But Rosie says they can be dangerous too. Here's why.
"My report is to highlight the dangers of the latest craze, squidgy water balls.
I think they are very unsafe and were recently banned at my school because of this.
In Teesside (near to where I live) two young girls have suffered severe injuries after the rope of the ball became entangled around their necks.
As it is made of such stretchy material it tightens around the neck and in both of the mentioned cases, the ball had to be cut free.
One girl had severe strangulation marks, scars and a burst blood vessel.
And the second escaped more lightly just with scars all round her neck.
So please think carefully next time you're playing with one."
Rosie, 11, Durham
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