MOREE

Maybe
https://www.mangago.me/read-manga/cat_therapy/

https://www.mangago.me/read-manga/give_birth_to_a_baby_wildcat_for_me_unless_you_want_to_see_me_go_insane/

https://www.mangago.me/read-manga/we_are_young/

https://manhuahot.com/manga/did-the-nerd-manage-to-flirt-with-the-cutie-today/

If you liked the fluffy elements of really recommend Involuntary Romance. It has a high school setting. But doesn't really have the animals shifter stuff. But it's really really cute too!!!