I think I've never written about this book.. Well, I'm not really a fan of english course books for primary school. Most of them are restricted to a few short topics and activities. I really like it better to create my own lessons most of the times with my own materials and Ideas. However, this course book as caught my attention three years ago. Not by the book itself but by the audio CD that comes with it!
The songs and chants are really great! The kids learn them fast and they always ask me to repeat them. It is a combination of nice songs with comic and dramatic voices.
I do think it is worth buying the project just for the CD! The activity book is also good. If I was forced to pick a course book for my students this would certainly be my choice.
Here in Portugal we can order the book from Santillana's site www.santillana.pt . I guess in spain it's the same... I don't know about other countries but I can tell you that the original publisher is Riachmond.