Our planet -- Our world's resources -- Humans and nature -- Nature activities -- Weather -- Extremes -- Kingdoms of living things -- All kinds of plants -- A closer look at trees -- Plant and fungus life cycles -- Animal life cycles -- Animal families -- Heads, bodies, and feet -- Feeding time -- Communicating -- Animal comparisons -- Animal clues -- Backyards and parks -- Fields and meadows -- Woodlands -- Rivers -- Oceans and coasts -- Rainforests -- Savannahs -- Deserts -- Mountains -- Arctic and Antarctic -- Protecting nature -- Working with nature.