Dr. Seuss, the pseudonym for Theodor Seuss Geisel, has written more than 60 books for children. His works are known for their clever rhymes, tongue-twisting words, and whimsical illustrations. They were educational and fun, but also contained many deeper meanings, presented in ways that kids and adults could understand. At the time of his death in 1991, he had sold more than 600 million copies of his books. 30 years later, he still remains one of the most popular children’s book authors of all time. His books have inspired movies, TV shows, musicals, and even a theme park. Here’s our ranking of the best movies based on his books.

6 The Cat in the Hat (2003)

A scene from The Cat in the Hat
Universal Pictures

The Cat in the Hat is a 2003 adaptation of the classic book. It’s directed by Bo Welch and stars Mike Myers as the Cat, who creates mischief with two siblings. While fun, the movie’s downfall is with its plot. The book is short, and beyond a cat making chaos with two children; it doesn’t have much of a plot. Because of this, the movie added various subplots to lengthen it, but they weren't particularly good, which brought the movie negative critical reviews. However, the movie does do a great job with its casting and visuals. The extensive makeup on Myers is almost frighteningly realistic, and he brings a lot of life to the character of the Cat. The movie’s visuals are also fun, and capture the whimsical spirit of the book.

Related: Will These Children's Books Ever Get The Adaptations They Deserve?

5 The Grinch (2018)

A scene from the Grinch
Universal Pictures

The third adaptation of the book, How the Grinch Stole Christmas!, the 2018 animated feature The Grinch is directed by Scott Mosier and Yarrow Cheney. It features Benedict Cumberbatch as the voice of the Grinch, who steals Christmas from the cheerful Whos of Whoville. The digital animation – the first Grinch adaptation in this medium – is bright and colorful, and even makes the Grinch seem cute, though he still has his miserable spirit that changes at the end. This version treads on the familiar, and does it well, even becoming the highest-grossing Christmas movie after its release. It doesn't add much to the story, but it's a solid take on it, with lighthearted humor and a strong Christmas spirit.

4 How The Grinch Stole Christmas (2000)

How The Grinch Stole Christmas
Universal Pictures

How The Grinch Stole Christmas, the 2000 adaptation of the Grinch story, is directed by Ron Howard. Jim Carrey stars as a live-action version of the character and gives an excellent performance as the mean-turned-nice Grinch. He’s equally funny and scary, in impressive makeup, and is the highlight of the movie. This version also brings more backstory and characterization to the classic story, along with the Grinch and Cindy Lou Who having a bigger relationship, which helps him see the good in Christmas. It received mostly positive reviews, though some thought the movie went too dark. It remains one of the highest-grossing Christmas movies of all time, and one of the most heartwarming.

Related: Best Christmas Movies of the 2000s

3 The Lorax (2012)

A scene from The Lorax
Universal Pictures

The Lorax is a 2012 movie directed by Chris Renaud. It stars Zac Efron as Ted, a boy in a world of fake trees, who ventures out in search of a real one to impress his crush. While on his journey, he meets the Once-ler, who tells of his own experience cutting down trees to make money, drawing the ire of the Lorax. The Once-ler gives Ted his last seed, which Ted plants in the hopes of restoring the trees. The colors and animation are playful and capture Seuss’ whimsical spirit. Its issue of deforestation is handled well for a children’s movie, though some critics felt that the movie didn’t go deep enough, and that adding traditional movie tropes of romance detracted from the book’s message.

2 Horton Hears a Who! (2008)

A scene from Horton Hears A Who
20th Century Fox

This 2008 adaptation of Horton Hears a Who! is the first feature-length Seuss adaptation to be fully, and digitally, animated. Jimmy Hayward and Steve Martino direct Jim Carrey as Horton, an elephant who discovers a village of people living in a speck of dust. He sets off on a journey to keep the speck safe, as the audience gets to know the speck's inhabitants. As the first digitally animated feature, Horton excels in its visuals, which earned lots of praise. Both the animal and human characters have that classic Seuss feel to them, and the setting is equally colorful and magical. It's also one of the funnier adaptations, and one that remains strongly faithful to its source material.

1 How The Grinch Stole Christmas! (1966)

A scene from How the Grinch Stole Christmas
MGM Television

While not technically a movie, the 1966 TV special of How the Grinch Stole Christmas! is simply too good not to include. Directed by Chuck Jones and Ben Washam, with the iconic Boris Karloff as both narrator and Grinch, it establishes the Grinch as he’s known today. Seuss was reluctant to make the adaptation, but agreed because he had previously worked with Jones on cartoons for Warner Brothers. Jones, a popular cartoonist who also served as the film’s animation director, added more color to the book’s simple palette, creating the green Grinch and the colorful world of Whoville. The film looks like the pages of the book come to life, and delivers a simple, yet heartwarming tale about Christmas. Though not a smash success when it aired, its popularity has only grown. It remains not only the definitive Grinch adaptation, but the definitive Seuss adaptation.