We are given the answer to this question in Chapter 10, when Miss Edmonds picks Jesse up and they drive to the art gallery together. We need to remember though that Miss Edmonds has been the only adult to identify and encourage Jesse's artistic talent. She is the one person who has really sought to show Jesse that his talent his something special and to try to communicate to him that this is a gift. It is clear that Jesse's family are too wrapped up in their own problems to really notice Jesse's gift. Therefore, when they are in the car together, Miss Edmonds asks Jesse if he has been to a gallery before, and when he replies in the negative, she says something very revealing:
"Great," she said. "My life has been worthwhile after all."
For a teacher like Miss Edmonds who entered the profession precisely because she wanted to nurture talent and characters like Jesse, having the opportunity to take somebody like Jesse, who clearly is a gifted artist, to a gallery gives her immense satisfaction. This is why she is so pleased that Jesse hasn't been to a gallery, so that she can be the one to introduce him to all of these great artists and paintings.