Although leaving the school where she spent her entire teaching career was a wrench, at least she can rest easy in the knowledge that she made a difference - a fact validated by her receiving the Ted Wragg teaching award for lifetime achievement at this summer’s Welsh Platos ceremony.

Headteacher Dewi Jones nominated Mrs Ham for the award.

“She has been a great champion of the school. She is supremely optimistic, and that has been a powerful force in encouraging us to continue to make improvements here,” he said.

“She has made a huge contribution to setting and maintaining standards.

Perseverance and energy are the hallmarks of her personality. She belies her age, and her stamina is the envy of many younger people.”

Mrs Ham was responsible for bringing in a number of policies that improved discipline, such as compulsory school uniform, banning of jewellery, and the introduction of a “time-out” room for low-level disruption.

“Because this is a priority-area school it has developed a certain reputation, and this can be hard to shake off, even when improvements are in place,” she said.

Enhanced standards at the school have seen the population grow from a low point of 300 pupils during the early 1990s, to the current 750.

Mrs Ham feels she has been able to have an influence at Glyn Derw because successive heads have given her the freedom to act as she feels appropriate. More heads should give their staff such opportunities, she says.

“Too often those in charge have too tight a rein on the school. I think they would be surprised at how people shine once they are given some freedom to express themselves.”

Another vital tool is praise, she adds. “Whatever age we are, we need to be told that we are doing a good job. The pupils need to be praised for doing well, but it’s easy to forget that teachers need that kind of encouragement too.”

Although her career in teaching spans more than a quarter of a century, her working life began as a secretary at the BBC. Only when she started work as a school secretary did she consider teaching, and eventually business studies.

Widowed last year, Mrs Ham was not particularly looking forward to retirement until the arrival of her grandson, Harry. But from September on, the nine-month-old can look forward to having his “besotted” granny as his child-minder.

She was beaten to the Plato by Harry’s dad Andrew, her son. He is assistant head at Monmouth school and won the award in 2001.