Sticks and stones - Sarah Mlynowski

The second book in a hilarious and heartfelt new series about a group
of magical misfits!
Nory Horace is nine years old. She's resourceful, she's brave, she
likes peanut butter cookies. Also, like most people in her magical
world, she's able to transform into many different animals.
Unfortunately, Nory's shape-shifting ability is a bit...wonky. And
when she flunks out of her father's own magic academy, Nory's forced
to enter the magic equivalent of the remedial classes.
But Nory and her new classmates are going to prove that upside-down
magic definitely beats right-side up!