The Cat in the Hat, Sam-I-Am and The Lorax invaded elementary schools across Suffolk on Wednesday as schools celebrated Read Across America.

The celebration takes place annually, but not all schools participate every year. It is often themed after the famed author and illustrator Dr. Seuss, as it takes place on his birthday.

“We don’t do it every year, to make it extra special,” said Michele Waggoner, the library media specialist at Oakland Elementary School.

Oakland and several other elementary schools hosted guest readers throughout the day on Wednesday. They included Superintendent Dr. Deran Whitney, Mayor Linda T. Johnson, School Board members and the Norfolk Tides mascot, Rip Tide.

Whitney read “Hooray for Diffendoofer Day!” at Oakland.

“It’s my favorite,” he said. The book follows the eccentric teachers at a school who teach their students “to think” in unconventional ways. The students at the school must do well on a standardized test, or else Diffendoofer will be closed and they will be sent to Flobbertown, a school that does not have a playground and where all the students dress the same.

Johnson read “The Lorax,” a book about a factory that turns truffula trees into thneeds, causing air and water pollution that runs away all the residents of the town.

“Do you think there’s a lesson here?” Johnson asked Mrs. Springfield’s class after she read the book. “We need to take care of the environment so it will be here for our children and your children.”

School Board member Linda Bouchard, with her therapy dog Scout, read “On Beyond the Zebra” at Oakland. The story features 20 made-up letters that come after Z in the English alphabet.

She said she enjoys bringing her dog to the schools and teaching about how to treat animals well — and about the joy they can bring to their humans — as well as reading to the children.

“It’ll drop your blood pressure at least 10 points,” she said of petting a dog.

The PTA at Oakland got involved as well, making Dr. Seuss-themed crafts to decorate the school and gifts for guest readers.

Students also enjoyed green eggs and ham sandwiches during lunchtime at the schools and other activities, including a door contest at Oakland. Teachers decorated their doors in Dr. Seuss themes, and students were able to vote on the winner.