A Simple Thermometer
You will need: Glass tube, cork, bottle, bowl, water, and kettle.
Thermometers depend for their action upon the fact that fluids expand when heated and contract when cooled. Most thermometers use mercury to register degrees of heat. We will make a simple form of thermometer using water.
Pour a cupful of water into a bottle and stand the bottle in a bowl. Drill a hole in the cork and insert a length of glass tube that reaches well below the surface of the water when you cork the bottle tightly.
Now heat some water in a kettle and pour it over the bottle. This will heat the water in the bottle and cause it to rise in the tube.
Now pour cold water over the outside of the bottle and the water will gradually sink lower in your home-made thermometer.
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!