My daughter LOVES these books and this one is one of her faves. She loves to fill up the pen and then reveal all the hidden images. She will even watch the pages as they dry, waiting excitedly for the opportunity to colour them in all over again. I like these books because we seem to get several uses (and many hours of play) out of each one before the pages start to get too wrinkly and damaged, so they seem like a good use of our kid entertainment budget.