Does My Head Look Big in This? by Randa Abdel-Fattah (NY: Orchard Books, 2007).
This book reminded me a LOT of Looking for Alibrandi [by Melinda Marchetta] because 1.) it's about living with a hyphenated identity as a teen; 2.) it takes place in Australia; and 3.) There is a crazy old lady who ultimately teaches the main character, Amal, a lesson about life by revealing her own big secret.
The plot centers around Amal, an eleventh grader who decides to take up the practice of wearing hijab (a head-scarf in her case) to demonstrate her faith, and the reactions of family, friends, and strangers that ensue, thereby causing her to rethink many aspects of her own life in addition to who she thinks she is.
While Amal’s exploits do not even remotely resemble those of the often, shall I say over-exposed teen in some ya fiction, her sense of ethics feels authentic. I also appreciated the frank discussion of the importance of faith in her life without it becoming too preachy nor something that teens who do not practice her religion (or any at all) cannot relate to.