Ola liked her class very much. The room was colourful and the children's drawings hung on the walls. One day, when everyone went inside, Ola noticed that her beloved backpack with the bunny was gone! Mrs Marta, their teacher, said calmly: "Don't worry, Ola. Let's look for it together. Maybe the backpack is hiding somewhere." Kuba, Zosia and Antek started to search the room. They looked under the desks, behind the blackboard and in the lockers. Suddenly, they heard quiet giggles coming from behind a large box of building blocks. As they got closer, the coloured crayons themselves began to roll across the floor, forming a mysterious pattern. Is this an ordinary day at school, or is the room hiding some kind of surprise? All the children looked at each other with wide-open eyes when.... something moved behind the curtain in the corner of the classroom!