Pio Peep! Rimas tradicionales en espanol by Alma Flor Ada & Isabel Campoy is a book with CD that we have back from the days when I was trying to teach a two year old Bruce Spanish. This is a very pretty book, but not one that I would recommend purchasing if you are serious about teaching your children Spanish.
My main problem with this book is the way the authors have chosen to translate the Spanish nursery rhymes into English. They are very upfront about their decisions, as explained on page 7: “To preserve the charm of the original rhymes, the English version is not a translation but a poetic re-creation. In some instances, the details are different, but the re-creation remains true to the essence of the original”. Meaning of course, that you can’t listen to the English versions of the songs and poems as a way to learn what the Spanish versions mean.
On the plus side, the Spanish songs and poems they chose are classics such as “Cinco lobitos” and “Tengo una muneca”. But still, I’d save your money on this book and choose something else.