Have you checked out our STEM Collection? It is a special group of picture book fiction and nonfiction for preschool and school age kids that focuses on STEM subjects.
One of the nonfiction series, intended for younger children, is Seeing Patterns All Around. This series provides examples of different types of patterns in a variety of settings.
There are many beautiful pictures inside each book such as
this one from Patterns in the Desert,
this one from Patterns in the Park,
and this one from Patterns in the City!