When Jem takes Scout to school for her first day, what order does he give her?
Scout explains Jem's request at the beginning of Chapter 2:
Jem was careful to explain that during school hours I was not to bother him, I was not to approach him with requests to enact a chapter of Tarzan and the Ant Men, to embarrass him with references to his private life, or tag along behind him at recess and noon. I was to stick with the first grade and he would stick with the fifth. In short, I was to leave him alone.
This is Scout's first experience with the public and private side of Jem. Previously, she had witnessed only one identity, because Jem had no one to impress at home. At school though, Jem is higher in the social hierarchy due to his age, & he has no desire to be connected to his younger sister. It is yet another step in Scout's road to maturity, & one of the first signs that Jem is indeed older than herself. The age difference may not matter much at home, but at school it puts them in completely different worlds.