"The Yuckiest, Stinkiest, Best Valentine Ever" is a delightful picture book that captivates young readers with its bright, colorful illustrations. The story follows Leon as he unravels the truth about his secret crush, engaging readers to eagerly turn each page. The book effectively explains the concept of a secret crush in a fun and relatable way. I particularly enjoyed the use of a valentine heart as the protagonist, cleverly navigating through Leon's encounters using the concept of measurement. Overall, this book is a great choice for young readers, blending humor, charm, and a valuable lesson about friendship and crushes.