I must admit I picked up this book as it was one of the new books listed in my local library.
I did somewhat enjoy the book but the wittiness of the author may be too hard for children to get it.
However, Grumpy Frog tells the story of a "not grumpy" frog who hops all day, and claims to be happy. In the midst of it all, readers are introduced to his friends, which include fellow frogs, a crocodile, and a rabbit. Through his adventures, children can learn about colours (literally and figuratively), feelings, and the theme of friendship (which is why I tagged this book under 'concepts').
There's also the underlying theme of being okay with not coming in first all the time.
I also love the illustration of this book.
In all, a fun book to read along with your children.