Recommend Reading Books for Kindergarten.
Bob Books Set 1: Beginning Readers
Little Cat Feet, Good Fences, Maybe a Mile, (These are from the older Keys to Reading series — great controlled readers, but harder to find . You might check used bookstores or libraries for them as a bridge to first grade or even beginning First Grade. This is one of the best resources I used.)
Yellow Fish, Blue Fish (Level PP1) by Laurene Krasny Brown, illustrated by Marc Brown.
My Friends the Frogs (Level PP2) by James Marshall.
Grab That Dog! (Level PP3) by Tomie dePaola (with Sherry Forman Litwack).
These are short, illustrated readers with simple stories, poems, and activities (like making a bookmark or hat) to build early reading skills, sight words, and phonics in a fun way. They were part of a larger 16-volume Heath Reading program from the late 1980s/early 1990s.
Availability:
These are out of print but still available used on several sites:
Amazon, eBay, AbeBooks, ThriftBooks, and Etsy often have individual copies (prices typically $6–$50+ depending on condition).
Use market+Archives.org