I need help with the theme of fear in the novel The Chrysailds.

For the theme of fear, I would first start by discussing Waknuk society itself.  The entire society operates based on fear.  They have a fear of change.  Not necessarily societal change (although the society is fairly stagnant), but of genetic change.  Waknuk society is terrified of allowing any genetic variation that is considered outside "normal."  That's crazy.  They obviously didn't pay attention in 7th grade biology class, because that's where students learn that the advantage...

For the theme of fear, I would first start by discussing Waknuk society itself.  The entire society operates based on fear.  They have a fear of change.  Not necessarily societal change (although the society is fairly stagnant), but of genetic change.  Waknuk society is terrified of allowing any genetic variation that is considered outside "normal."  That's crazy.  They obviously didn't pay attention in 7th grade biology class, because that's where students learn that the advantage of sexual reproduction is genetic diversity.  But I digress.  Anybody who is genetically different enough to stand out is either killed or banished from Waknuk society to the Fringes.  That's why Sophie is terrified of people discovering her extra toe.  

That theme of fear is a two way street.  Let's use David and his telepaths as an example.  He and his friends are fearful of being found out.  They don't want to wind up dead.  But the other side of the street is that the Waknuk's are fearful of David and his abilities.  They have a right to be fearful as well, because the Sealand woman tells David that it is more or less fate and destiny that David and his kind will see the destruction of "normal" humans.