A theme (also known as a motif) is the main driving idea behind a poem. A theme or motif is not a summary of the poem, or a detail from the poem, but rather the emotion or motivation behind the poem. The theme might be "unrequited love" or "the power of traditions," but it wouldn't be "putting up walls between property lines," or anything else that specific.
Answer:
You could probably figure out that the boys in the story are English schoolboys, and were more than likely being evacuated from their home country to escape the possibility of atomic warfare. (Does this help?)
The second or fourth one I'm not sure
