They are about 770 miles apart as the crow flies, almost as far as London is from Madrid, but these two teachers have much in common: small classes, willing pupils and close-knit communities. Their schools are surrounded by breathtaking scenery, they are reliant on air and sea travel, at the mercy of the weather and are in remote locations. These are the teachers at the furthest ends of the British Isles.

Louise Simmonds is in her third year teaching at a school in St Agnes, the most south-westerly of the Scilly Isles, and is the sole teacher for five pupils. Gordon Thomson has been teaching on Unst, on the northernmost tip of the Shetland Islands, since 1978 and, as an English teacher, has class sizes that most teachers would envy - about 10 in each. Both owe their island jobs to holidays.

Gordon was not long out of teacher training when he went to Unst for a holiday in Easter 1978. Visiting the ruins of 16th-century Muness Castle on the island’s south-east coast, he started talking with the caretaker and happened to mention he was a newly qualified teacher. On such a small island, the caretaker knew the school was looking for a new teacher. “She said they were looking for a teacher at the school. So she rang the headteacher up there and then and I talked to him on the phone,” Gordon says. For a 22-year-old working in rural Sutherland when jobs were hard to come by, it seemed a good option, although originally only a temporary post.

“They needed a teacher for a month in the summer, and in that time a member of staff left and I was offered the job, so I took it,” he says. “I just thought it was the chance to stay somewhere else, and although I grew up in Edinburgh, I like rural places. In those days they had council houses allocated for teachers, so I was quite happy to stay. I had my own classroom and a chance of a house near the school.”

Louise, 52, made her move to island life at a later stage in her career.

She had taught on the mainland for 31 years, near Guildford in Surrey, but holidayed regularly in Scilly and fell in love with the islands. “We said if a job came up, I would have a go. One did, so I thought I would,” she says.

Louise was offered the position and moved to St Agnes three years ago with her husband, a retired food scientist, and two of her three children. One is now a boat-builder, the other an inter-island boatman, while the third is studying on the mainland. The school is technically a base, part of Five Islands School, which has its main site on St Mary’s, the largest island.

A new pupil started this month, bringing Louise’s class up to five, aged four to 11, although when she started there were just two. After teaching in a school of 360 it was a culture shock, and she admits she has found it harder than she expected.

“It is much more difficult with fewer children. It is totally working with each child as an individual. You have to make it more exciting to get them motivated, and there is always another pupil who needs you. It’s like spinning plates and it’s the most demanding and challenging job I have had,” she says.

The pupils on St Agnes, a community of just 68, are gentle and willing to learn, she says, and the islanders have high expectations for their children.

Gordon, 51, believes the children on Unst are the same as children everywhere, although he recognises his experience of teaching on the mainland took place almost 30 years ago. “I suppose they’re a bit more respectful here; you don’t have a lot of trouble, although I don’t have anything to compare it with,” he says. “I might find it a bit of a shock to go to a city school, where teachers probably have to be stricter and firmer.”

Gordon is deputy head and the only English secondary teacher at Baltasound Junior High, a school for three to 16-year-olds that has about 30 primary age children and 40 secondary. School numbers have been halved since the closure of the island’s RAF base last year, which reduced Unst’s population from more than 1,000 to 500.

The presence of the base meant that when Gordon moved to the island it had a thriving social scene, making it easier for the 22-year-old to settle in.

He married a local girl and they have two children, one now a weekly boarder at Shetland’s only sixth form, in Lerwick. The seaport is a 50-mile trip by road and sea, and Aberdeen a 14-hour ferry ride away. But Gordon says the remoteness has never bothered him. He returns to Edinburgh about once a year to visit his family.

“Shetland is not that primitive a place. There is enough happening, there are shops, social events, a leisure centre. If you want bright lights, ready-made entertainment and cinemas you are not going to find them here, but otherwise you just get on with it. You know everyone in the community, it does not take long to get to work, and there’s a lot of wildlife and a lot of scenery,” he says.

Being part of a small community does mean less privacy, but that was one of the reasons that drew Louise to Scilly. “It’s the most social place in the world, but they’re very good at giving you your own space,” she says. “When I’m not at school, I’m not the teacher; you don’t go to the pub and find somebody wants to talk about their kids.

“I came from an area where nobody knew their neighbours and now I know everybody on the island. A lot of people would hate it, but living here is something else.”

As the only teacher on St Agnes, she says there is a risk of going stir crazy, but a weekly staff meeting at St Mary’s is a chance to get together with teachers on the other islands and swap ideas.

The weather, meanwhile, brings its own problems. Shetland is on the same latitude as southern Greenland, but the Gulf Stream means winters are more wet than white, although they are also dark. The biggest weather villain is usually the wind. Gales cause occasional power cuts and can stop the ferry running, making one of the most remote parts of the British Isles even more isolated. “If you know bad weather’s on the way, you make sure you have enough food in the house,” says Gordon. “You just have to be prepared, but I like it here and I don’t want to move anywhere else.”