One approach for creating thesis statements that compare/contrast the stories "The Magic Barrel," "Where Are You Going, Where have You Been?", and "A Small, Good Thing," is to compare/contrast them on the basis of their major themes. The major themes of these short stories may be said to be (1) resurrection and new beginnings ("The Magic Barrel"), (2) doom and living death from violent manipulation ("Where Are You Going, ...?"), and (3) mortal death leading to kindness and forgiveness ("A Small, Good Thing"). A thesis comparing these stories based on theme might be something like this:
Whereas "A Small, Good Thing" offers hope of kindness and forgiveness after a tragic event and "The Magic Barrel" offers hope of new beginnings and resurrection after wrong choices and unhappy beginnings, "Where Are You Going, Where Have You Been?" offers fear of hopelessness through brutality and living death in the midst of a quiet home where everyday things are traded for desperate fear.
Another approach for comparative thesis statements for these three stories would be to compare/contrast their mood/atmosphere. Mood and atmosphere are synonymous terms used interchangeably. Mood/atmosphere is determined by the author's choices of setting, vocabulary, diction (high [educated], mid [everyday], low [casual, slang, dialect]), imagery, symbols, etc. For example, the mood in "Where Are You Going, ...?" starts out innocently enough then turns sinister and threatening. This can be compared to/contrasted with the mood and mood changes in the other two stories. You can also compare/contrast based on symbolism, narrator's voice and point of view (first person, third person...), or types of characters, among other approaches.