What are a few examples of similes in "The Destructors"?

Similes definitely add to the artistry of "The Destructors"  by Graham Greene.  He uses them to help describe the scenes in the story and to characterize the boys.

Simile #1: "A smaller bomb and some incendiaries had fallen beyond, so that the house stuck up like a jagged tooth..."

This simile is describing the site of the bombings in London during WWII. The neighborhood the boys live in has been ravaged.  One remaining home has survived the destruction, and describing it like a jagged tooth implies the devouring of the area, ugliness and pain.

Simile #2: “It’s got a staircase two hundred years old like a corkscrew. Nothing holds it up.”

Trevor knows about suspended staircases because his father is an architect, but he needs to describe it in terms the boys can understand.

Simile #3: “We’d be like worms, don’t you see, in an apple."

Here Trevor is describing the destruction they will do on the house. Worms are on the inside of an apple, not visible on the outside. Likewise, the boys will destroy the house from the inside with no visible damage on the exterior.

Simile #4: "The loo stood like a tomb in a neglected graveyard."

This simile speaks to the destruction of the area.  The outhouse is small in the midst of the rubble.  The comparison to a tomb gives it the image of death, which the war has caused.