The last tree town / Beth Turley.

Enhanced descriptions from Syndetics:

"A tender novel about how negotiating fine lines--between friendship and a crush, between sadness and something crueler--is part of the mixed bag that is growing up." -- Shelf Awareness
"A sensitive story of family, friendship, and personal growth." -- Kirkus Reviews

From the author of If This Were a Story comes a heartfelt, coming-of-age novel about sisterhood, friendship, and the stories behind our journeys that connect us to one another.

Cassi has always been proud to be Puerto Rican, but when others comment on her appearance, telling her she doesn't look like the rest of her family, Cassi begins to question everything.

At school, Cassi finds a distraction in the Math Olympics, where she is able to do what she loves and soon befriends Aaron, the new boy who tells her stories about all the tree towns he's lived in. Just when everything seems to be getting better, a painful video goes viral and Cassi wonders if Mapleton is just another stop on Aaron's list.

As the seasons change, Cassi must learn to solve the pieces of her life that are varied and emotional and at times, beautiful. And even when they don't equate, reveal a rewarding answer.