Based on the search results, "Oh, What a Busy Day" is a book by Gyo Fujikawa that features all kinds of kids doing all kinds of kid things, such as playing, pretending, learning, crying, and laughing. The book is filled with silly jingles, fun rhymes, imaginative ideas for games, and gentle lessons on kindness and friendship. According to reviews, it is an extremely fun book for both parents and children, although it may be a bit long for just one sitting. There is also a creepy story about children dying in the woods included in the book, which may not be suitable for all readers. Overall, "Oh, What a Busy Day" is a childrens book that celebrates the joys and challenges of childhood through colorful illustrations and engaging storytelling.