Guardian Angel by William McCauley

Grades 6-9. Red-haired, freckle-faced Markus Simmons worries about things that many middle-school boys obsess about: When will my body fill out? When will my voice lower? When will I grow body hair? He wishes that puberty would hurry up and take care of things. That would be his ticket to hanging with the cool kids in school. But when three of the A-listers ask him to work with them on their Holocaust project for social studies class, he sees his chance.

Inside he suspects that they want him on their team just to get at his ailing grandmother, who was in Auschwitz during the Holocaust and has the tattoo on her arm to prove it. When Markus approaches his grandmother to ask her questions about her time in the camp, she violently refuses to discuss it. He’s torn between the peer pressure at school and the loyalty he owes his grandmother. In the meantime, his former best friends begin to distance themselves from him, and his mother’s behavior becomes increasingly bizarre.