Mrs Riding is deeply concerned both for her own prospects and for those of the children she teaches. “I’ve always put children first,” she says, “and believed they were in my care. But I don’t want to have to work until I’m 60, because, with the best will in the world, you don’t know if you will have the strength then.”

After taking time out of teaching when her own children were young, Mrs Riding has less than 20 years’ contribution to the teachers’ superannuation fund. She had expected to have had this made up to 20 years, which, she says, would have left her “reasonably comfortable”. Going early will reduce her already modest pension prospects.

As much as the money, Mrs Riding regrets the manner of her likely departure. “I would have been happy to go out with dignity when I felt I was still doing a good job,” she says. “I feel now I’ve been pushed into a corner, applying to go at the end of March.” She is worried about the children she will leave behind if her request is approved. “I’m concerned for the class. They’re Year 6, and they’re going to be taking SATs, which is important for them and me. In all conscience, I’d have preferred to have stayed and seen them through that. It’s going to be quite traumatic. Whoever’s made these changes hasn’t really considered the effects it will have.”

* Althea Rannie, 54, has taught for 23 years at Comberton Middle School in Kidderminster, Hereford and Worcester. She is a “floating teacher” in the 620-pupil school, and has a 40-period week.

Prompted by the planned changes to pension rights, she has applied to retire by the end of March instead of in the summer of 1998 as previously planned. “I knew I’d be hard pushed to go on to 60,” she says. “I don’t want to have to go on grounds of ill health or mental breakdown or a heart attack later. These proposals have forced my hand.”

She adds: “It makes more difference to the school than to me. The graveyard is full of indispensable people, and I’m not classifying myself as one of those. But there are two of us going on early retirement, and my philosophy was to see the year through. It had been agreed that I could take a temporary contract for the summer term, but it now looks as though that won’t be possible. It’s the goalposts moving yet again.”

Ms Rannie will lose some pension entitlement by her earlier departure. Although by December she would have made contributions entitling her to 30-eightieths of her salary, she now falls just short of that. “It makes a difference of a few hundred pounds per year,” she says, “which on a small income becomes significant.” Ms Rannie has other investments maturing when she is 55.

None the less, she says, she will have to continue to earn, somehow. “I’m happy to do some supply teaching. But I would do anything. I’m a sub-aqua diver, so I might go for a professional qualification in that, and teach it.”

* Roger Canton, 51, has spent just over 30 years in teaching, the last ten in further education. He had not planned to retire until his mid-fifties, but in the light of the likely end of early retirement has enquired about going before the end of March. Managers at the College of North West London, where Mr Canton teaches leisure and tourism, circulated all 400 teachers, asking whether they wanted to go, to consider their position, or to stay. Mr Canton, who was “undecided”, now has to decide whether to end his career in teaching. “My wife and eldest son are fed up with hearing about it,” he says.

The college, which was already set to “downsize”, is offering a redundancy payment and a pension enhancement of three years and four months. Mr Canton believes he would have an annual pension of Pounds 11,000, reduced to Pounds 8,000 after tax. It’s a sharp drop from a current take-home pay of Pounds 19,000, and if he accepts the offer the father-of-three will need to supplement his pension. “The offer won’t leave us in paupery,” he says. “But I don’t think it’s a fair arrangement. It smacks of illegality.”

Mr Canton is indignant at the proposed shift of the pension cost to the employer. “I feel the Government has hijacked 30 years of my contributions. I didn’t pay it to the College of North West London, I paid it to a bona fide, recognised, respected pension arrangement with the Government.” If he takes redundancy, he could supplement his pension through supply teaching. Or he might try something completely different. “Delivering, driving a van. Something that gets me out and about.”

What would happen to the students is unclear. “I’d be leaving 58 students approaching the end-of-course assessment, for which I am an organiser. Who would tidy up the bits and pieces I don’t know.”

* Sue Greening, 46, is a class teacher at Dean Gibson RC Primary School in Kendal, Cumbria. A teacher since she was 21, Ms Greening had planned to retire at 50.

“I think nearly 30 years is long enough for anyone in full-time teaching, ” she says. Having planned her future, she feels cheated by the government proposals. Her mortgage will be paid off by the time she is 50, and she had planned to use early retirement to spend more time with her father, who lives in Spain.

“When you’re in your twenties and they do this, you have time to change your financial plans,” she says. “With three years to go, there’s not enough time to make taking out another pension a viable proposition. If I was 25, I could cope with it more easily.”

Finances apart, Ms Greening, like many others, feels a sense of dread at the prospect of being forced to carry on in a job she currently enjoys but which she knows can be demanding. She has 33 children aged 9 and 10 in her Year 5 class, and next year will have 36. “I do enjoy it,” she says, “but there comes a point where you’re ‘taught out’. There’s a big difference between the prospect of another three years and another 13 years. I think I should be allowed to go when I want.

“If you talk to any teacher, most are planning their retirement. I think the politicians should ask themselves why so many want to take early retirement. ”

* John Harvey, 52, is head of science at the Highfield School in Letchworth, an 11-18 comprehensive with 850 pupils. Mr Harvey has taught there for 26 years, and is leaving at the end of March. “I’m very lucky,” he says. “I had intended to retire this July, then the head called me in in late October and asked if I was aware of these changes, which I wasn’t. She advised me to contact the personnel department at Hertfordshire County, and they have agreed to March 31. The head and chair of governors have been brilliantly supportive.

“I’ve sneaked under before the gate dropped. It was all right initially, because I agreed I’d go back for the summer to see the year out and have a nice, clean hand-over. The latest is that they might even be stopping that. I feel lucky to have just made it, but I would like to do the summer term.

“The agreement was that, to all intents and purposes, I’d be doing the same job until July. If I can’t, particularly for the exam classes, I’d be sorry. It would be difficult to find a physics teacher to pick up the reins for those last few weeks, so the pupils will suffer.

“I do feel in the public eye we wouldn’t get a lot of sympathy. I think the public perspective is ‘So what?’ But early retirement was possible, and it’s unfair of government to arbitrarily change the rules. I think teaching is a young person’s profession. I don’t feel particularly old, but I feel I’ve come to the end of my teaching life. I think what these changes will bring is a lot of long- term sickness, in which case no one will benefit.”

* Leontine Cox, 51, is a deputy head at Southfield School, an 11-18 comprehensive in Workington, Cumbria. With 29 years of English teaching behind her, she had applied for retirement next summer but brought forward the application in December and now wants to go at the end of March.

“I’d always hoped to do this,” she says. “My daughter has just had a baby; my mother looked after my children and it has always been my ambition to be able to do the same. I want to enjoy my grandchildren and allow my daughter, who’s also a teacher, to continue to work.

“The morale among older teachers has plummeted since these changes were put forward. Colleagues in their late forties and fifties are really worried. Once you’ve made the decision to retire at a certain age, the idea that you may not be able to go is really devastating. And this came out of the blue.”

Mrs Cox, after consulting her headteacher, changed her application to beat the deadline. Although she has not had a decision from the governors, she is hopeful. “I’ve always given my all to the profession. The idea that I would be forced to go on without feeling committed and enthusiastic is a real downer. ”

She concedes that 50 is relatively young for retirement but believes teachers are a special case. “It may be an early age to retire,” she says, “but it has been available and people had legitimately had that expectation. We’re a profession that feels we get a lot of brickbats and blame, and teachers my age certainly feel it’s got harder. I’ve always taught in not-easy schools, which I’ve always enjoyed, but it has got harder, mainly because of lack of money.

“I would feel very cheated if I wasn’t allowed to go. And if we have growing numbers, losing commitment and energy but forced to stay, the whole service will suffer.”