Kids in the Bronx and the rest of the city headed back to the classroom Tuesday.It was the first day of classes at public schools across the city. Parents and students in the Bronx had a special visitor when they walked through the doors Tuesday.Mayor Bloomberg was in the borough to usher in the new school year. He decided to greet parents and students at P.S. 53. The mayor was also at M.S. 22 to discuss the state's investment in education.Bloomberg says he wants to tell parents about changes they can expect for the upcoming year. He says school bureaucracy will be streamlined and the money saved will go right back into the schools. Other changes, he says, will be obvious, such as new science labs and 3,700 additional seats.Related information: The New York City Department of Education