Allegory - C.S. Lewis was deeply religious, and his story is a thinly-veiled allegory of the Christian Bible, with the lion Aslan, for example, symbolizing Jesus. He was killed ceremoniously, dying for the sins of the Pevensie children, but he returned to life.
Allusion - The story takes place while World War II is being fought on Earth, specifically during the Blitzkrieg.
Protagonist - The main protagonist among the Pevensie children is Lucy, as she urged her siblings to visit Narnia and to help save Narnia from the White Witch.
Round Character - Aslan, the lion and creator of Narnia, possesses deep wisdom and guides the Pevensies in the fulfillment of the prophecy, showing compassion for the children, particularly Lucy.
Flat Characters - Mr. and Mrs. Beaver give the Pevensies shelter, inform the children of the prophecy about them, help them escape the White Witch's wolves, and lead them to Aslan's camp, serving to move the plot along.
Dramatic Irony - Lucy's siblings did not believe her when she spoke of the magical land in the wardrobe. Professor Kirke suggested she was being truthful, and they discovered that she was when they stumbled into Narnia.
Reversal - The Narnians are losing their battle against the White Witch's army, but the tide is turned when Aslan returns from death, joins the battle, and defeats the witch.
Mood - There is a sense of urgency throughout the story, from the need to escape the Blitzkrieg to rescuing Edmund and reaching Aslan's camp. This urgency is interrupted with moments of calm, such as when Lucy first enters the peaceful forest with snow falling gently around her.
Figure of Speech - "At the name of Aslan, each one of the children felt something jump in his inside" - Describing a feeling as one's stomach leaping is a common figure of speech.