The night before the first day of school, Sara Vanhove tossed and turned, her mind already racing through the excitement of the next day.

There would be new school supplies, neatly organized in the desk labeled with her name. There would be a bright classroom, dotted with cheerful posters and decorated with a baseball theme, welcoming the “team” of first-graders to their desks. When the school day began, there would be happy shouts, a few tears, and a steady stream of parents offering hopeful smiles as they waved goodbye.

And for the first time, she’d swallow her nerves, smile and offer a greeting: “I’m your teacher.”

For the 28 first-graders in Vanhove’s class at L.H. Tanglen Elementary School in Minnetonka, Tuesday marked the start of a big year.

With kindergarten behind them, they were old pros at this school stuff, moving up from picture books and coloring projects to reading and math, science and social studies. (“Science!” one of Vanhove’s students exclaimed, when informed about the year’s curriculum plans. “I love science!”)

As they settled into their desks, a few students jumped up to greet friends they recognized from kindergarten. Others launched into in-depth conversations about pets and favorite foods and birthdays with classmates they’d just met.

In one corner of the room, two of the first-graders traded stories about how early they’d arrived at school.

“The teachers have been here longer than anybody,” one observed.

They were right: Vanhove had already been in her classroom for nearly two hours Tuesday morning, checking over for a third or fourth — or 20th — time that she had everything in order. She’d been waiting for this day for months, since she got the job offer from Hopkins Public Schools just as she wrapped up her teaching degree at the University of Wisconsin-Madison.

But really, she’d been waiting for this day even longer, since she was a kid growing up in Edina, buying classroom instruction books at the school book fair so she could pretend to be a teacher when she played “school” at home. After spending weeks preparing her classroom and meeting some of her students and parents at a school open house, Vanhove was feeling more eager than ever about her career choice.

“It’s really cool and surreal that I get to do this,” she said. “It doesn’t feel like a job for me.”

As the school day began, Vanhove sat in a rocking chair as the first-graders gathered around her on a colorful mat. She deftly caught their attention — “one, two, three, eyes on me” — and offered praise: “I would have thought you were all in first grade last year!”

Then, she pulled out a book called “First Day Jitters,” the story of somebody who is so anxious about the first day of school that she tries to hide under the covers and stay in bed. On the last page, it’s revealed that the nervous character isn’t a student: She’s a new teacher, named Sarah.

Vanhove looked around at her students and asked if any of them had been too excited to sleep the night before. Several raised their hands, and she assured them that the feeling was normal — and that it would eventually go away.

“You guys are going to make friends, you’re going to learn, and there’s no reason that you’re going to feel that way the whole year,” she said.

Pausing, she then quietly added: “That’s pretty cool.”