Maybe a weird request — can anyone suggest a good book about Teshuvah for an older child that is strongly anti-religious?

While I would be happy if my child showed some interest in Jewish celebrations and observances, I am more interested in them growing to be a mensch. In that vein, I am looking for age-appropriate (middle-school reading level or so) books that speak meaningfully about Teshuvah from a non-religious, non-spiritual perspective but still hopefully with something of a Jewish flavor.

My child is very interested in intellectual pursuits and loves humor so books that place purposeful positive action in a historical context or books with lots of jokes in them are preferred, especially over books that are overly simplistic or moralistic.

They also feel very very strongly about fairness and social/economic justice so books that address Tzedakah and/or Tikkun Olam in the same manner would also be greatly appreciated.

If you don’t have any specific book recommendations, any tips handling a “devoutly” atheistic/anti-religious child in a respectful manner that helps them grow into a loving responsible Jewish adult would be greatly appreciated.