Balloon in a Bottle
You will need: A balloon, two glass tubes, rubber band, bottle or large jar and cork.
Secure a balloon to the end of a glass tube with a rubber band, as illustrated.
Now take a bottle or large jar with a tight-fitting cork. Drill two holes through the cork and insert the tubes (A and B).
A smear of butter on each length of tubing will assist their entry into the cork and also ensure an airtight fit. Another smear of butter around the cork will similarly ensure an airtight fit in the mouth of the jar.
Place the end of tube A in your mouth and suck
the air from the jar. As the air is withdrawn you will see the balloon steadily
swell. The outer air entering tube B inflates the balloon as it tries to
maintain the pressure of air inside the jar.
Children learn best through doing
Before children can understand a thing, they need experience: seeing, touching, hearing, tasting, smelling; choosing, arranging, putting things together, taking things apart. Experimenting with real things.
Old-time school teaching used only words and the teachers thought children knew something if they could repeat it. Now we know better. To reach practical understanding we do not need to use many words with young children.
Children are clever. They learn a lot, without being taught. The greatest skill - to be able to talk, to communicate is learnt outside school. In the classroom it's the children who need to talk the most. Unfortunately it is the teacher who does most of the talking!