Parents and community leaders were invited to see inside the first high school to be built in Suffolk for 20 years as the final phase of the building was completed.
Pakefield High School opened to year-seven and eight pupils in 2011 on the former middle school site.
But since then school leaders have had to fight to get the extensions that they need, with diggers and building work an ever-present distraction for children studying for their exams.
However now the final phase is finally complete, with students guiding parents and people from the community on tours of the new facilities.
New headteacher Anthony Walker told those gathered: 'With the investment the community has made and the determination you have shown to set up a fantastic school in the community, I feel humbled to be standing here as the new headteacher.'
He added that it was 'important to recognise the successes staff and students have had at a time of great challenges for the school', pointing to its strong first sets of GCSE results.
Keith Monaghan, chairman of governors at the school, told those gathered there had been 'many, many challenges along the way - but I hope as you look around the facilities, you'll agree it's been very, very worthwhile'.
Those facilities include modern classrooms and computer rooms and a new sports hall, as well as an all-weather pitch outside.
The aim is now to encourage organisations and people within the neighbourhood use the facilities, truly making it a community school.
Lowestoft mayor Nick Webb said: 'We have a duty of care to ensure young people have the best facilities we can provide.
'The building does that - and that's thanks to you.'
Got a Lowestoft story? Email andrew.papworth@archant.co.uk
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