While having fun with snow and cleaning up afterwards Betty Spaghetti saw how Benny the Baker was making bread. Wondering how it was possible for the bread to rise, she asked Benny what he was using. "The magic behind the rising bread is sugar and yeast, but mainly yeast."
Yeast?? She thought. What is that? So just as before, Betty Spaghetti began investigating.
Here is what she found:
What is yeast?
Let's experiment
Experiment 1: The Science of yeast
Instructions:
- Pour a 1/4 cup of very warm water in each bottle.
- Add 1/2 a teaspoon of table sugar to each jar.
- Add the packet of active dry yeast to one of the containers.
- Place a balloon over each jar.
- Let the learners predict what is going to happen.
- The bottle with yeast will begin bubbling. If the learners put their ear to the bottle they will hear the bubbles from the yeast.
Experiment 2: Let's blow up balloons with four different kitchen ingredients.
Instructions:
Bottle 1
- Pour an inch of warm water in the bottle and dump the entire packet of yeast in.
- Swirl the yeast around and then add the teaspoon of sugar. Swirl again.
- Put the balloon over the mouth of the bottle and let it sit in the sun.
- Let the child observe and tell what they are seeing.
Bottle 2
- Pour a couple of inches of vinegar.
- Prep the balloon by using the funnel to fill half of it with baking soda.
- Put the balloon over the mouth of the bottle and press to dump the baking soda in the bottle.
- Let the child observe and tell what they are seeing.
Bottle 3
- Half fill the bottle with Diet coke or any soda. It is best to use a freshly opened bottle and pour out the soda you don't want to use.
- To prep the balloon dump a pack of Pop Rocks into it.
- Put the balloon over the mouth of the bottle and dump the Pop Rocks into the bottle.
- Let the child observe and tell what they are seeing.
Bottle 4
- Half fill this bottle with the rest of the soda from the previous bottle.
- Put two Mentos in the balloon.
- Put the balloon over the bottle and dump the mentos into the bottle.
- Let the child observe and tell what they are seeing.
Line up the bottles next to each other to see what is happening to all of them.
Ask the following questions:
- Which bottle blew up the balloon the best?
- Which reaction made the most carbon dioxide.

