In Wonder, did Jack sit next to August in homeroom?

The answer to your question about Wonder can be found in chapter 14, which is called "Locks." We are in the middle of reading about August's first day of school. August has already had a tour of the school, so it is easy for him to find his homeroom even if he does have his head "hung way down" so that people will not see his face. August takes a seat in the back in order to avoid as many stares as he can. When his acquaintances Charlotte and Julian come in the room, they sit together in the front. The room begins to fill with students. No one chooses a desk next to August until Jack arrives. Jack walks directly to the back of the room and sits beside August. No one else chooses to do so. In fact, two students cram into one desk in order to sit elsewhere.