Norton High School’s $34 million addition and renovation project is on schedule and on budget, with completion projected for December 2013, according to interim Superintendent Chris Martes and School Committee member Margaret Werner. The construction manager and owner’s project manager took the School Committee and staff members on a tour of the project Monday. Norton is building a new cafeteria and science laboratories and making upgrades throughout the building. Students will be able to use the cafeteria after February vacation, though the kitchen may not be ready immediately, Martes said. The labs will also be open, but initially they will be used for regular classroom space so the older part of the building can be renovated. All told, the project is about half done, Werner said.