Materials cover primary and secondary colors.  For preschool to kindergarten.

Books
All The Colors Of The Rainbow by Allan Fowler
Brown Bear Brown Bear, What Do You See? by Bill Martin Jr.
Color by Ruth Heller 
The Color Box by Dayle Ann Dodds
A Color Of His Own by Leo Lionni
Freight Train by Donald Crews
The Gift of Driscoll Lipscomb by Sara Yamaka 
Growing Colors by Bruce McMillan
Is It Red? Is It Yellow? Is It Blue by Tana Hoba
Little Blue and Little Yellow by Leo Lionni
Mouse Paint by Ellen Stoll Walsh
My Many Colored Days by Dr. Seuss 
The Nature and Science of Color by Jane Burton.        
Planting a Rainbow by Lois Ehlert

Realia
Colors Unit workbook
Color Bear puzzle
8 Color bean bags

Book & Cassette
Mary Wore Her Red Dress and Henry Wore His Green Sneakers by Merle Peek

Video
Harold and the Purple Crayon