I knew the name instantly. And when his picture flashed up on the screen my worst fears were confirmed: the young man who had been charged with murder was my former student.

When I knew him he was just five years old. Blond, bright, always smiling. He would come into school each day full of enthusiasm. You would never have guessed the horror of his home life. Both his parents were on drugs and he was largely left to fend for himself.

Working in schools where this type of situation is common, you try to persuade yourself that you can make a difference. You spend extra time attempting to push these students on, to improve their aspirations and to encourage them to believe that a life exists beyond the neglect and disruption they are experiencing.

And sometimes you think you may have managed it. You work with government agencies and other teachers and people in the community to really improve the life chances of that young person. In time, you are rewarded by talk of wanting to go to university, or comments about how much they enjoy school.

But then the children get older. Outside influences become more pronounced. Understanding of their own situation increases. And at this critical time, when the child starts secondary school, the education system pulls back. Groups are larger so teachers’ knowledge of individuals lessens and the relationships between teachers and students naturally become weaker. The community and parental links to school are fewer - there is not the time to form them and no channels established to maintain them. Home visits? Virtually unheard of.

I have seen so many intelligent children become drug-addled wasters after becoming lost in their teen years without the parental or school guidance they require.

There must be a culture change in secondary schools so that these students get the help they need: a replacement family unit. Otherwise there will be many more teachers sitting watching the news at the end of another busy day, seeing what former students have become and wondering what future awaits their current class.

The writer is a teacher in south-east England.