The definition of setting is the time, place, mood, and climate. In the book Ender in Exile, The time is late fall at the beginning of the school year on earth. (No information as to where on earth) The mood is sad & confused and the climate is cold.
I know the time the book takes place in is fall because The character, Valentine Wiggins, has just started the next school year. She is writing essays and doing homework and complaining about her teachers because she is so much smarter than them.
Most of the characters are on earth. The mother, father, brother, and sister are on earth. Ender is in space. He just came back from saving the world and is saying goodbye to his comrades. His family cannot decide whether Ender should come home or stay in space.
The reason being, If he comes home and starts going to school, he could never have a normal life with everyone asking him how and why he saved the earth from aliens who tried to invade. However, if his parents let him stay out in space, They would probably never see him again.