WHEN 82-year-old Yvonne Foster applied to teach the BBC’s economics editor to dive she thought nothing more would come of it.

Just a week later she was at the pool where Robert Peston learned to swim, telling him to hug his ears, lift his head and slide in to the water like a sea monster.

The idea for the challenge originated on Radio 4’s PM programme last year, when Mr Peston confessed he found it hard to understand his energy bill.

One listener came into the studio and explained how the tariffs were calculated, prompting the programme’s editors to try and uncover other gaps in Mr Peston’s knowledge which PM listeners might be able to shed light on.

He came up with five things he wanted to learn, including diving, landscape painting and learning how to do the voice of Mr Punch.

Mrs Foster said: “He was such a wonderful man to teach, he was full of fun and we had a lot of laughs.

“It only took me about two hours to teach him to dive and he was quite nervous at first, but he definitely learned to dive and he was just so pleased with himself.”

Mrs Foster, from Ampleforth, has been teaching for 40 years. After hearing that Mr Peston wanted to learn, she applied and was invited to Park Road Swimming Pool, in north London, to give him a lesson.

She said: “They said they chose me because I specialise in teaching nervous swimmers and because of my experience.”

Mrs Foster, who still swims several times a week and takes part in swimathons to raise money for Marie Curie Cancer Care, began teaching swimming in 1974 and has since taught her three children, six grandchildren and the children of friends.

She has also written a children’s book called Hi...I Want to SWIM! which is laminated so it can be taken to the pool.

She said she hoped Mr Peston was still diving.

“He started off without knowing how to dive, but within two hours he was definitely diving. He couldn’t believe it.”

Mrs Foster specialises in helping nervous children, teenagers and adults overcome their fear of the water and become confident swimmers.

She has numerous techniques, including encouraging children to pretend they are mermaids or sea monsters.