First of all, the genre of a fantasy written in letters with a one sided view coming from a superior demon to a lesser one is unique, making it a seletion for a high school reading. Also, no young adult should miss the priceless commentary tht Lewis provides through his persona about faith. As a Catholic school teacher, this book provides interesting discussion, especially when it is cross-referenced with the Catechism.
The classic theme of good versus evil presents an interesting view of the battleground that exists in each man's soul. Thank God for Lewis and Tolkien's discussions over a cup of tea. Too bad we have no record of those discussions, or do we?

I should first like to esplain the reason why I have rated "The Screwtape Letters" to be a 5. I cannot say how any other person will say after reading this book whether it ought to be rated a 1 or a 5. I, however, do know that after reading it the first time liked it very much and '5' in my opinion represents that fact that I very much enjoyed reading this book.
Now about the book.
"The Screwtape Letters" is an agglomerate of letters from one demon, Screwtape, to his nephew, Wormwood. Screwtape is a demon ranking higher above his nephew and therefore his letters are filled with advice to Wormwood on how he ought to go about tempting his human.
The dialogue between the two demons (though the reader never actually reads Wormwood's responses) really puts a new perspective on the reality of a spiritual battle really taking place from day to day.