To make a cannon ball we need newsprint, toilet paper, white glue, sand, transparent film, brush, black paint and water.
The first thing to do is 2 or 3 pieces of sheets of paper.
We wrap the pieces of paper on a sheet of paper, making a ball about 10 cm in diameter. Also pick up a piece of transparent film to wrap the ball of paper.
Then we make a mixture of water and white glue in equal parts, and we make pieces of toilet paper.
With a brush, paint the ball of paper with the mixture, putting up pieces of toilet paper and paint it again with the mixture, we do 2 or 3 more times. We will leave an opening about 2 cm at the top of the ball.
Let it dry the ball,and  when it is dry bring out newsprint inside the ball, also the transparent film. We can use scissors to remove the paper.
Now we need a small bag and sand.
We put the bag inside the ball and then fill it with the sand.
When the ball is full of sand, we will cover the opening with more mixture of glue and water and toilet paper.
We let it dry.
Paint it black.
And this is the result, a heavy cannon ball.