Here is a wonderful big book that I use in my classroom. My students love a reading break on the carpet with a big book so everyone can see the illustrations and view the printed text as well.
My second graders love the big book ABC ¡Ya Me Lo Sé! by Yanitizia Canetti. ISBN 0395787114, published by Houghton Mifflin. It is expensive (~$45) but worth every penny. It is a progressive rhyming story with beautiful illustrations using the alphabet and children's first names in an elementary school setting. Fun! DO SEARCH BY ISBN NUMBER.
Another good big book is ¡ABRAPALABRA! This colorful big book is full of creative approaches to presenting vocabulary to help content-wise with any theme.
