Black boys are being let down by white, middle-class teachers who negotiate with them rather than impose discipline, the head of a charity that helps disadvantaged youngsters has warned.

Tony Sewell, a teacher who wrote the book Black Masculinities and Schooling: how black boys survive modern schooling and founded the charity Generating Genius, raised his concerns at a debate asking: "Why do black boys keep getting excluded?"

Research for the Timpson Review of school exclusions found that after accounting for other factors, black Caribbean pupils were around 1.7 times more likely to be permanently excluded than white British children.

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Dr Sewell said: “One of the reasons why we collapse the exclusion rate is the fact that too many liberal white teachers are negotiating with our black boys."

He said this was "instead of saying ‘this is where it is, I expect so much of you, I have so much expectation from you, you are going to get to the highest university, but you are going to do it in the structure. I am the teacher, I am the adult in this space. You are the child in this space, and this is how it works’.”

He described schools where black children do well as “high-ritual, high-discipline, high-expectations”, and added: “This is the structure that we had in the Caribbean.

"This is the structure that we had in West Africa, and I think where our children collapse, and where our boys collapse, is in environments where in fact the teacher is our friend and we are kind of negotiating all these things,” he said at the Festival of Education at Wellington College,

Other panellists raised concerns that the education system is institutionally racist, or highlighted the lack of non-white people in school leadership.

Malcolm Richards, an exclusion officer at Devon County Council, said: “The fact is our system is structurally and institutionally racist. It is in many ways designed in a way to marginalise and discriminate against lots of different groups.

“That is an uncomfortable fact, but I think it is one that we have to begin to accept in our practice, in our policy, in our Ofsted framework, in our curriculum, we have to acknowledge that fact.

“I don’t think that acknowledgement has happened yet, and only once that acknowledgement has taken place then some true dialogue around co-creation of curriculum, of practice, can take place.”

Hussein Hussein, a teacher who founded CAPE Mentors, an educational support service for students finding it difficult to access education, said the overwhelming majority of headteachers are white.

He said that if there was better representation “there’s a better ability to empathise, and when you can empathise you can make decisions that aren’t blanket”.