Teacher's pets

The girls are dismayed when their teacher is out sick and they have a substitute. Mr. Z makes goofy jokes and can't keep the class under control. Worst of all, he doesn't say anything when mean Darlene makes fun of Kate and Lucie. Luckily, once the girls turn into dogs, Kate and Lucie learn they can save the day--and even make a new friend. The girls are dismayed when their teacher is out sick and they have a substitute, especially when Mr. Z makes goofy jokes and can't keep the class under control. The coauthor is Joanna Cole. Book #2