Montessori's Land, Air, & Water lesson is a simple one that requires labels and samples of each. The Air dish appears empty but is filled with what the element we can not see or taste, although we know it is there because it fills our lungs. You may also want a balloon and stick with a ribbon attached. Blow up the balloon and ask your child "What is in the balloon to make it big?" Then you may blow at the ribbon and ask your child "What made the ribbon move?"
The next lesson will be to introduce your child to a globe. You can use the same labels and element dishes to compare the land and water to the land and water on the globe. Remember that Europe and Asia are a single continent in terms of land mass. However, for political reasons it is considered two continents in some countries, while other countries call it Eurasia.