Miss Bindergarten and the Very Wet Day (Penguin Young Readers, Level 2)

"Today is a very wet day. Miss Bindergarten's class stays inside while the rain falls hard outside. Finally, the rain stops and the class goes outside to play. It's not long before Matty and Patty slip and fall in a puddle! Miss B. and Coco are there to help, and when the girls get up, a huge rainbow has formed in the sky!"