The 27-year-old primary teacher waded into the sea at Dover on August 15 and arrived in France just under 12 hours later after swimming 22 miles.

He said: “After a year of training it was quite emotional when I finally touched the shore. All these people were out walking their dogs and came down to congratulate me. They were all speaking in French and I thought ‘Crikey, I’ve swum to another country’.”

Mr White, a teacher at Kentisbeare primary in Cullompton, Devon, had lots of good luck cards from pupils before he set off and is expecting to raise around pound;3,000 in sponsorship to promote swimming at the school.

The English Channel is one of the busiest shipping lanes in the world, with 600 tankers passing through every day and 200 ferries crossing it. And then there are the jelly fish to contend with. “They range in size from tennis balls to dustbins. You can swim around the dustbin-sized ones but you don’t know about the little ones until they brush over you,” said Mr White.

An enormous tanker went streaming past him. “I was just a few metres away from this wall of metal. It was quite frightening.”

But there were some beautiful moments too for Mr White - such as seeing the sun rise as he left the white cliffs behind.

Mr White is a member of the British Long Distance Swimming Association and competes in sea swims around the country. Last summer he took part in the 21-mile, two-way Windermere swim.

Pupils at his school swim from reception through to Year 6, and by the time they are 11 years old, most have exceeded the national curriculum requirement to swim 25 metres and can do at least 100m.

Mr White said: “We take them to Honiton swimming pool regularly, more or less from the moment they join the school. By Year 6 it is almost like having a swimming squad.”