There's a lot of potential for classroom use of this book--to launch a community service project, to nurture small group discussions, and as a mentor for writing informational text. I'd read this aloud to students in the primary and perhaps intermediate grades. It's long so I think I'd read 2-3 parts each day for a week maybe and pose questions for small groups to discuss like "What did you learn about one group that is helping the community?" and "Why is their work important?" and "How did the author/photographer reveal the importance of this work?" and "One of Ancona's messages is that volunteer work can be fun. How does he reveal this?" and "How does this group's work differ from that one's?"
Ancona's writing is clear and cohesive. Close reading of a section of this text might benefit students who are seeking to write about community organizations or doing research on a similar topic. For example, students could read a particular section (each section is about a different group doing community work) and discuss, "How does Ancona introduce the group or organization?" and "What does he describe or explain?" and "How does this help the reader develop clarity?"
Also, if you are launching a unit on community service, there's great vocabulary in the book to highlight - shelter, community farm, food depot, etc.
One disappointment--but not a deal breaker. I tend to think of Ancona as an author/photographer of the Mexican American experience. (He was born in Brooklyn and his parents were Mexican immigrants.) I shouldn't pigeonhole him. My apologies. At the same time, I was disappointed that a larger variety of faces were not revealed in this book. I did notice a variety of names that could represent different ethnic groups, but visually there wasn't much distinction except for one group towards the end of the book (from the Boys and Girls Club). It's not a deal breaker - I'd still use the book. There's just room for some critical thinking with students about the author/photographer/publisher choices. And perhaps, there is more diversity than I'm aware of - maybe a discussion with students would reveal this to me.