Plans to expand Felpham Community College have been submitted to West Sussex County Council.
The demand on school places across the county has increased in recent years, with Bognor identified as a hot spot.
Following a public consultation, approval has now been sought for a three-storey building at the college, in Felpham Way, along with an extension to the existing science block, the addition of a first floor to the changing rooms, extra playground space and parking.
Once approval is given, the ICT block will be demolished and temporary classrooms will be placed on the north playground while the building work is carried out.
The three-storey building will accommodate general classrooms as well as rooms for ICT, music, drama, sixth-form, technology and graphics.
When complete, the college will be able to take in an extra 60 Year 7 students per year, gradually increasing its numbers until it has an extra 300 children on the role.
The work will be carried out by Sunninghill Construction, co-ordinating with the county council.
Headteacher Mark Anstiss said: “We’re busy working with them to finalise the design so it can all start.
“One of the key issues is that planning consent may only be given in July, so they will only have a year to build it, so it’s going to be tight.
“All being well – and it is a very tight time scale – the new building will be ready and open from September 1 2019.”
Mr Anstiss said the changes were “exciting” for the students – and he and his team were looking forward to the improved facilities.
He added: “Although our school has improved over the years, I do get frustrated when I go to other schools that have better facilities – but once this is finished we will have as good facilities as other schools in West Sussex, and that’s what our children deserve.”
Mr Anstiss said the safety of the students was a priority for everyone, adding: “This will be a building site for a year and we need to make sure it will run smoothly and safely.”
Once approval is given, most of the heavy work will be completed this summer
Mr Anstiss said: “This is a once in a long time opportunity.
“The challenge for me is to try to imagine what education will be like in the next five years.
“I’m trying to think of ways I can future proof the building so that whatever happens we’ll be at the cutting edge.”