In the Observer letter, the parents said that while "there is room for improvement in some areas, the vast majority of the children are well adjusted, happy and well cared for".
They said the accounts being reported in the media "do not represent the spectrum of experiences and opinions of parents, students and teachers".
"To give just one example, the Department for Education (DfE) has (we understand from the school) already investigated a series of allegations and found no evidence to support the concerns about safeguarding practices," they wrote.
The letter also states that both MCA and MVPA rank highly on academic performances for children from disadvantaged backgrounds while SEND students do "exceptionally well".