Snow in August by Pete Hamill

Eleven year old Michael Devlin's world in 1940's Brooklyn was all about his Irish Catholic neighborhood.  Michael's dad was killed in WWll but he and his mom are doing fine.  Then one morning, on the way to church to fulfill his alter boy duties, he hears a request for help.  For the first time Michael meets the very orthodox Rabbi Judah Hirsch, a Czech refugee, who needs him to turn on the lights because it is Shabbos and Hirsch is not allow to work.  Although Michael's summer is filled with back street baseball, Jackie Robinson and Marvel comics, he finds himself drawn to the Rabbi and offers to be his "shabbos goy".  Michael teaches Hirsch about American customs and Hirsch shares the rich traditions of his faith - even teaches him a little Yiddish.  Their friendship is challenged by a tragic act of violence that forces Michael to recognize prejudice against the Jews but leaves him questioning its logic.  As acts of violence by a local gang escalate, Michael believes it will take the power of the Golem to make things right.  It is here that Hamill turns to a bit of magical realism to bring the story to it's rightful conclusion - rightful because this is the way you want the world to respond to the senseless evil we too often choose to ignore.