A young girl teaches her little brother several ways of writing and thinking about numbers, covering such concepts as addition, time, money, and tallies.
Provides information about waterfalls, explaining what they are, how they form, and where they are located, and looks at the risks scientists take in their efforts to study and learn more about waterfalls.
Provides information about volcanoes, explaining what they are, how they form, and where they are located, and looks at the risks scientists take in their efforts to study and learn more about volcanoes.