Malcolm at Midnight, book 2: Malcolm Under the Stars
W.H. Beck et Brian Lies2016

Now that Snip the cat is gone (but hardly forgotten), the classroom animals of the Midnight Academy are ready for things to get back to normal at the McKenna School. After all, protecting nutters (students) and lankies (teachers) is an around-the-clock job!
When a rare coin and a strange code are uncovered in the school, Malcolm and the Academy have another mystery on their paws. To find answers, Malcolm ventures into the dangerous outside world full of shady characters, new friends, and old enemies. Can Malcolm solve the mystery and save the school before it’s too late? Join Malcolm and company as they take on their most challenging assignment yet.