Grumpy Monkey Play All Day is a New York Times bestselling children's picture book by author Suzanne Lang and illustrator Max Lang, published by Random House Studio on September 24, 2024. It is part of the beloved Grumpy Monkey series and is recommended for children ages 4–8 (Preschool through Grade 3).

In this 32-page hardcover story, Jim Panzee wakes up one fine morning and declares that all he's going to do is play all day — avoiding tidying his branch, finding lunch, and even bathroom breaks. Jim swings with monkeys, sings with birds, and rolls around with zebras, always finding new friends to keep the fun going. But by the end of the day, dirty, itchy, and hungry, his best pal Norman gently reminds him that "Too much of anything can be, well, too much."

A relatable and silly story about procrastination and balance, this book is sure to delight children and parents alike. The book measures 10 x 10 inches (ISBN: 9780593709283).