Why is Jamie so hopeful? What did he want?

I'm not completely sure what you mean here. Ada became a village hero. For the first time Ada felt as if she were someone loved, as if she had been born with two good feet. Jamie is hopeful for this. Check this out below:

http://www.bookrags.com/studyguide-the-war-that-saved-my-life/chapanal012.html#gsc.tab=0