[ISLMA-Share] how damaged are books before you ask students to replace them?

[Email list for the Illinois School Library Media Association]

A high school student returned a book today that was clearly chewed on by a pet.  It is still readable, but there are teeth marks all over the cover of the book and parts of the bottom of the spine and pages are missing / warped.  How damaged does a book have to be before you require a student to pay to replace it?

Thanks!

Brooke Fleuette
Mercer County High School Library
Currently reading: Caraval by Stephanie Garber
Currently listening to: A Man Called Ove by Fredrik Backman