Press the 'Get bigger cat!' button to broadcast the message to get bigger. When the cat receives the message, it increases the size by 10. Press the 'Get smaller cat!' message. When the cat receives the message, it gets smaller by -10.
Copied from Lorraine Leo 'Integrating Scratch Into the Primary Classroom' Slide 28: https://docs.google.com/presentation/d/1eZqz0NgSET8SmfA3z0sdtEBLInh0s688glN7kwJG7Mc/edit#slide=id.g11702e09e_31
