Suffolk New Academy board quit before inspection
A board of trustees at an academy school resigned two days before its latest inspection, which revealed its action plans were "not fit for purpose".
Suffolk New Academy in Ipswich was put in special measures by Ofsted in December.
A monitoring inspection on 4 March found some improvements since a new principal was appointed last month.
A new board of trustees is due to take over in September.
The 650-pupil school, formerly Chantry High, became an academy in 2013.
Last year, 24% of its GCSE pupils got at least five A*-C grades, when the government's minimum target was 40%.
Serco, which carried out the follow-up inspection on behalf of Ofsted, said neither the school's improvement plan nor the sponsor/board of trustees' statement of action were "fit for purpose".
It did note school leaders "have worked hard to focus on starting to improve teaching and learning".
Craig D'Cunha took over as head teacher in February.
He said: "The inspector looked at an interim plan from September which was put in place until there was some stability.
"We're looking at adjusting the plan because there were some really strong points in it."
Suffolk New College, operating at the New Academies Trust, resigned as sponsor on 2 March.
Dave Muller, former trustee and principal at Suffolk New College, said: "We stepped down in line with our strategy to focus on providing vocational further education."
A new sponsor, the Active Learning Trust (ALT), is due to take over in September.