Time for school! / by Brian Biggs.

Enhanced descriptions from Syndetics:

From New York Times­-bestselling author and illustrator Brian Biggs comes the second picture book in the collectible Tinyville Town series.
In this next book in the preschool series, Time for School! shows how the whole community comes together for the first day of class. Mr. Meyer picks out his nicest sweater, Dylan ties his favorite shoes - and Mrs. Martinez, the crossing guard, has been waiting for this day all summer long. She joins the bus driver, the school principal, the lunchroom and playground staff, and, of course, all of the teachers, as they welcome the children of Tinyville Town Elementary back to school. And when a new girl shows up, everyone knows just what to do to make her feel right at home.
Brian Biggs' read-aloud Tinyville Town series launched in 2016 with three books: the world-establishing picture book Gets to Work! and two board books, I'm a Veterinarian and I'm a Firefighter. In addition to Time for School!, the series has grown to include two additional board books, I'm a Librarian and I'm a Police Officer.
With a nod to the busy world of Richard Scarry and the neighborhood feel of Sesame Street, the Tinyville Town series has become a favorite read for preschoolers. Using bold, comic-influenced art to illustrate a growing, thriving, diverse city full of interesting people, these books are ideal for story time and class discussions about occupations and community helpers.