We have a number of poetry collections for children, including two that I believe are among the best: A Child's Garden of Verses: A Classic Illustrated edition and Read-Aloud Rhymes for the Very Young. None of them seemed to interest my son, though. I'd read a bit here and there, but he was always ready to move on and never picked them up himself.
I found a copy of this book and decided to risk it because I do love his illustrations. This is a book of poetry about (surprise, suprise) animals, each paired with a large collage in the vibrant colors we've learned to expect from Eric Carle. My son has enjoyed paging through this book on his own and has asked us to read the poems to him. Seals, sharks, whales, elephants, lions, sea turtles, giraffes...all the "favorite" animals of childhood have a place in the book. I think he also appreciates shorter selections with only one or two on each page. It allows him to relax and enjoy the poem and the illustration without clutter.
The poems themselves are from a variety of poets, times and types, so my son is being exposed to lots of different aspects of poetry. I think it's a great first book of poetry for him and I've learned to watch for poetry collections that feature what he loves rather than ones that seem great just to me (though we'll get to those eventually).
Eric Carle's whimsical and gorgeous illustrations are paired with a variety of poems, all about animals. The poets range from Shakespeare to Rudyard Kipling to Jack Prelutsky. This book would be a fantastic addition to any child's poetry collection.