Halfway through the most recent documentary in Channel 4‘s Lost Children series, which offers a glimpse inside an alternative provision school in Berkshire, Philip Larkin’s This Be the Verse drifted into my head.

As the poet wrote back in 1971, “They fuck you up, your mum and dad.” It could have been written for Courtney, a 12-going-on-18-year-old girl from Liverpool who, after being excluded from her primary, has ended up at High Close, a special residential school run by children’s charity Barnardo’s.

Courtney (pictured) is diagnosed as having attention deficit hyperactivity disorder and behaviour problems, which result in a statement of special educational needs. The footage flits from her disrupting class to her threatening to kick someone’s head in. “It’s like there’s a little cell inside my head that says ‘don’t care’,” Courtney tells the interviewer.

The programme tries to make sense of why Courtney is the way she is; why the “little cell” is in her head. It introduces her mother, Sara, a 28-year-old single mum who gave birth to her daughter at 16; her grandmother, Jean; and her 81-year-old great-grandmother, Edna. It is a unique look at how three generations of abusive relationships, broken homes and unhappiness may have led to Courtney being Courtney.

Lost Children is a welcome departure from recent Channel 4 documentaries such as The Undateables, which play strongly on the freak-show element of their subject matter. The programme at least tries to explain why some children just cannot behave, and why the term “troubled” often fails to capture the full range of issues contained within a child from a disrupted background. But with only an hour-long slot, it doesn’t go deep enough.

It does show, however, intentionally or not, how the education system can fail the most vulnerable children. After being excluded from mainstream education, Courtney is sent to High Close, but when they cannot deal with her behaviour she is passed on again.

The film finishes with Courtney ending up in a special school, where we are told she is making good progress. Her mother says she hopes her daughter will not follow the path she took and get pregnant at a young age. But such cycles are difficult to break. “They fuck you up, your mum and dadThey may not mean to, but they do.”

Lost Children: Courtney will be broadcast on Channel 4 on 31 July at 10pm.