Not a homework question per se, but DD8's class is reading "Number the Stars," historical fiction set in 1943 Denmark, and said that according to her teacher, World War II began in 1942.

This is one of her gifted teachers.

Since I just happen to be on volume 6 of Churchill's pseudo-autobiographical account of the entire war, it didn't take much convincing for DD to take my word over the teacher's.