Delayed building work disrupted children's education and left one Merseyside school "looking like a refugee camp", an MP has claimed.
Frank Field, Labour MP for Birkenhead, has urged exam boards to take account of the problems when marking papers
Jarvis is a year behind in its work at eight schools in Wirral, which are being funded by private money.
Mr Field said the worst affected was Prenton High School. Jarvis said it "regrets any disruption" caused.
Mr Field told the BBC he went to the girls' high school in Prenton at the beginning of the academic year and said he thought the conditions were unacceptable.
'Leaking toilets'
"I can only describe it as being like going into a refugee camp," he said.
"There was chaos - there was mud all around.
"The building didn't function properly - at times it was freezing cold, the lavatory system was not working properly and leaking through ceilings."
On Monday the school said it had laid on extra revision lessons for pupils to help make sure they were ready for their exams.
Jarvis said some of the delays have been caused by the discovery of asbestos in a couple of schools.
Wirral Council said the deal with Jarvis would lead to better schools in the area and added it was working to keep disruption to a minimum.