A headteacher said he and his team were "very excited" about plans to expand their school.
Following a public consultation, a planning application has been submitted to West Sussex County Council to expand The Angmering School.
Demand for school places across the county has increased in recent years, with the coastal strip recognised as a particular hot-spot.
The work includes a three-storey teaching block, extension to the changing block, and an infill extension between the performing arts department and the dining hall to provide a dance studio/stage.
It should be finished in time for the start of the September 2019 term.
Headteacher Simon Liley said: "We are very excited about the new facilities which this project will deliver for the school and local community and are looking forward to working with the local authority and construction company to manage the project.
"The target is to have the main elements complete and ready for occupation by September 2019, with some of the minor elements forming a much smaller second phase if required."
Once complete, the school will be able to increase its intake from 252 children per year to 270 per year.
The extra facilities will be: five science labs, five art classrooms, nine general teaching rooms, additional PE changing rooms, improved toilet facilities, a larger dining hall (doubling as a dance/drama studio) and an expanded and refurbished drama studio.
The work will be carried out by Sunninghill Construction Ltd and Mr Liley said they hoped to "break ground" in July.
The expansion will be paid for by the Department for Education out of its 'basic need' budget. No money will be taken from the school's budget.
Mr Liley said: "We are fortunate that the main construction area is to the east of our site and close to the existing boundary.
"This will mean minimal disruption to lessons and learning for our students and staff.
"There will of course need to be carefully controlled entrance and exit from the Bramley Green pedestrian gate during the construction phase in order to keep everyone safe.
"As with any such building project there will be some short-term disruption for local residents but the construction company are very sensitive to this and will work with West Sussex County
Council to ensure that noise and disturbance are kept to a minimum and within normal working hours wherever possible."
He added: "We thank all of our community partners for their continued support during this exciting phase of our progress."
To read the application - WSCC/019/18/A - log on to www.westsussex.gov.uk .