The furniture is arriving, teachers want to get into their new classrooms, and the new Thompson Elementary School is expected to be ready for the first day of school next month. “It’s a hopping place right now,” Superintendent Kathleen Bodie said of the final preparations at the kindergarten-Grade 5 school. The $20 million project began in late 2011 with the demolition of the 55-year-old Thompson School on North Union Street. District officials said the new building was needed to accommodate the town’s growing student population, and to provide better space for state-mandated prekindergarten programs for special needs students. Bodie said the contractor is putting the final touches on the building, and the work is expected to be completed on time and within the project’s budget. The new school is designed to hold about 380 students, and Bodie said it will be the first in Arlington to have an iPad for each student. The principal’s desk just arrived, other furniture is being delivered, and teachers are “chomping at the bit” to get into their new classrooms, Bodie said. The first day of school is Sept. 3. Full story for BostonGlobe.com subscribers.