LYNN – Susanne Garrity is so excited for the first day of school she hasn’t been able to sleep, but Garrity is not a student returning to classes today: She is the Cobbet School’s new principal.”The kids are going to be so happy to be in this building,” Garrity said Tuesday as she showed off Cobbet’s freshly painted hallways and classrooms.The 630 students trooping back into the Franklin Street school are among almost 15,000 returning to classes today. All students except pre-kindergarten and kindergarten students will be back to school by Thursday, and pre-K and kindergarten classes begin on Sept. 9.In addition to a new principal and fresh paint, Cobbet is starting the academic year with new windows and changes in the way school educators teach students and reach out to their parents.Garrity, a 15-year veteran of Lynn public schools, said a Spanish-speaking parent liaison will be in the school by week’s end meeting with parents and providing other assistance. Cradles to Crayons, a public school assistance program, provided new backpacks loaded with school supplies for every Cobbet student and Garrity has reorganized the school so that its different grade levels are clustered together in the school. Seven out of 10 Cobbet students are non-English speakers trying to master the language even as they learn to read and count. Garrity said their teachers will be supported by teams of specialists focused on reading and language assistance and other aid.”Our students need specialized instruction. We will have a lot of support for teachers,” she said.Cobbet students will also start the school year with enhanced technology. Classrooms have new computers, and students in classes like the one taught by Denise Firicano will learn their lessons as a group and break into smaller groups.Firicano said software available to her students will help them focus on study problems they are having difficulty mastering.Garrity is one of two new principals named during the summer break. Former school early childhood coordinator Marilyn Mahoney is overseeing the newly created early childhood center at 90 Commercial St. The center will hold an open house at 9 a.m. Friday, with buses taking parents and kindergartners from Brickett, Tracy and Ford schools to the center.Former Cobbet Principal Brian Fay is now Callahan School principal. Garrity on Tuesday credited Harrington School Principal Debra Ruggiero with preparing her for the Cobbet principalship.She is organizing a “family engagement council” at Cobbet to increase parental involvement in “the learning process” at Cobbet and said 138 parents attended an Aug. 29 “meet the principal” night.”It spoke volumes about how parents care about the school,” Garrity said.