1. Determine the theme and storyline: Determine the theme and storyline of the picture book according to the mathematical knowledge points in units 3 to 4. You can take "scores" as the theme and "sharing cakes" as the storyline.

2. Sketch the picture book: After determining the theme and story of the picture book, you can start sketching the picture book. Sketch is mainly the general framework and layout of picture books, including page numbers, contents of each page, illustrations and so on.