Start with high-confidence geometry books, then narrow by subgenre or adjacent topics.
Math Skillbuilders (grades 2 - 3)
Golden Books
Mcgraw-hill Education Geometry Review and Workbook
Carolyn Wheater
The Math Pact, Elementary
Karen S. Karp, Barbara J. Dougherty
The Summer Before Fourth Grade Workbook: Bridging 3rd to 4th Grade With 75+ Activities Math, Reading, Writing, Language Arts, Fractions, Geometry, and More!
Gold Stars
Math for Knitters
Kate Atherley
