Amazon calculates a product’s star ratings based on a machine learned model instead of a raw data average. The model takes into account factors including the age of a rating, whether the ratings are from verified purchasers, and factors that establish reviewer trustworthiness.
I had actually received the wrong item, but I was promptly refunded. Even so, I love this series of books and especially all the alliteration! It's very attention keeping for my 3-year old, and it constantly reinforces letter sounds.