Balloon Blow Up

I checked out a book about bread, weird I know, and inside it was an experiment with yeast.  I knew I had to save it so I would have something for the boys to do while home from school during Christmas break.  This was just the thing and they were excited to see the yeast at work.  You take a normal balloon and put it over the top of a pop bottle filled with warm water, sugar and yeast.  The gas from the yeast working blows up the balloon.

Here we are just getting started.  You can see the foaming yeast in the bottle.

Our finished balloon.  I didn't have the right size bottle, mine was smaller, so the inside of the balloon filled quickly with yeasty bubbles and became too heavy to hold itself.  The boys were amazed at the change regardless.  I'm sure they would like to do it again.

1 balloon

1 Tbsp yeast

1/4 cup sugar or honey

1 cup very warm water, plus extra for filling a mixing bowl

1 liter sized plastic soda bottle cleaned and dry

1 piece of string rubber band

Stretch the balloon by blowing it up and letting the air out a couple of times.

Stir the yeast, sugar, and 1 cup of warm water together, and pour it into the plastic bottle

Put the balloon completely over the opening of the bottle, and hold it in place with string or a rubber band.

Fill a mixing blow or pot halfway with warm water and put the soda bottle in it

The yeast will make the water in the soda bottle bubble and foam and watch- like magic the gas will blow up the balloon.