LYNNWOOD — Casey Campbell forced himself to eat a banana Tuesday morning despite his lack of appetite after a restless night of little sleep.

He’d planned to make his lunch but was too distracted. He didn’t even play with the puppies as he usually does.

On the way to school Campbell turned on the car radio but couldn’t remember what was playing.

Anxiety caused by the first day of school does that to people.

It even happens to teachers, especially when they’re one of the new kids on campus.

“I was nervous,” Campbell acknowledged between math classes at College Place Middle School in Lynnwood on his first day as a teacher. “I woke up at 5:30 and I had butterflies.”

Each year, there are about 1,500 new teachers across Washington, according to the state Office of Superintendent of Public Instruction. Campbell is one of this year’s class of teachers breaking in to the profession.

Schools opened in Edmonds, Darrington, Lakewood, Marysville and Stanwood-Camano Tuesday. Thousands of other Snohomish County students will return today.

Some new teachers are straight out of college; others, such as Campbell, take a circuitous route into the classroom.

Campbell, 31, majored in history at the University of Washington and was doing marketing research and financial analysis and reviewing architectural data for a Starbucks real estate division when he was bitten by the bug to teach middle school students.

So he went to graduate school, while holding down three part-time jobs, and became a math and science teacher, with a cut in pay, for the chance to guide more than 140 13-year-olds through eighth-grade math and algebra.

Tuesday was a bit of a blur.

Students had campus orientations in the morning. That meant classes were just 12 minutes long in the afternoon, just enough time for Campbell to introduce himself, lay down ground rules and learn a little bit about his students.

He allowed them to ask questions about him while he learned about them.

In one class, for instance, students volunteered that they were born in other countries: El Salvador, Mexico, Kuwait and Ethiopia.

Students learned he will use detention, believes in homework, won’t tolerate talking out of turn, and will make himself available twice a week after school for extra help.

Campbell, who had no cash in his wallet, also learned an important lesson: the cafeteria doesn’t take American Express.

Fellow teachers paid for his lunch tater tots and chicken nuggets and accepted him warmly.

Long after his students disappeared for the day, Campbell kept running the day’s events over in his mind. What went well? What he could do better?

Over the years to come, he’ll talk about his day in school and bounce ideas off of his wife, Kelly, a language arts teacher from Henry M. Jackson High School.

By 5:30 p.m., he was hoping to crawl in bed by 9.

Campbell had no regrets about his decision to leave the corporate world for the classroom.

“I’m tired,” he said. “It’s definitely a job where you earn your tiredness at the end of the day.”