Here’s the rule (rule, no exceptions ever) for German words with the “ie/ei” combination: always pronounce the second letter.
German teachers always seem to have a good sense of humor, and one of the first words you learn is “schießen”–pronounced "shEEsen–which means “to shoot.” This is not to be confused with “scheißen”–pronounced SHYsen–which means “to shit.”
Even though scheiße is about as common in German as “stuff” is in English, teachers always feign horror that you would dare curse in their class. You learn the difference pretty quickly 
English is sadly lacking in these hard and fast rules, so you’re never going to truly be able to get it right if you’re talking about an American with a German/Jewish name.