You will need: Three small bottles of similar size, three glass tubes, water, turpentine, rubbing alcohol, bowl.
Obtain three small bottles of the same size, each with a well-fitting cork. Drill holes in the corks to receive lengths of glass tubing.
Fill the bottles with different liquids, e.g., water, turpentine, rubbing alcohol, etc. Label each bottle and keep them away from flames.
Pour hot (but not boiling) water into a bowl and stand the three jars in the water. As the liquids become heated they will expand- but not to an equal degree.
The only escape for the expanding liquids is via the glass tubes. You will soon see which liquid wins this race of expansion. The alcohol will reach a higher point in its tube than the turpentine, thus indicating that it has a higher rate of expansion at the same temperature. The water will be found the least expansive of the three fluids.
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!