Clearwater High, a secret boarding school for shapeshifters.
Das Vermächtnis der Wandler (The Legacy of the Shifters). Brandis, Katja 7z
The "7z" in your request likely refers to the in her overarching walker universe, which is the first book of the sequel series: Woodwalkers: The Return (Season 2), Volume 1: Das Vermächtnis der Wandler (The Legacy of the Shifters). Clearwater High, a secret boarding school for shapeshifters
Carag, the cougar-shifter, returns as the lead character. Carag, the cougar-shifter, returns as the lead character
Katja Brandis (the pseudonym of German author Sylvia Englert) is best known for her high-stakes, shapeshifter fantasy series, which are popular with readers aged 10 and up. Her work typically follows young "walkers" who can transform between human and animal forms as they navigate secret boarding schools and environmental conflicts.
Carag's Transformation (The Woodwalkers Book 1) - Amazon.com