Ros Bastow was seven years old and a pupil at Pantglas, when her name was Ros Davies. Now 57, she had never spoken about what happened that day. A week before the anniversary, she decided she needed to. So she wrote a poem and shared it with friends. On the 50th anniversary, she hopes to see the teacher who helped her to safety for the first time in decades.

I haven’t spoken about this in 50 years. I’ve never talked about it to family or friends, not my parents, not even my husband. If you were to ask, they would probably say ‘She copes really well with it’. I wasn't really coping with it.

It started off with the weather. Living in that valley, you knew when the weather was bad because you always had the clouds hanging over the top of the mountains. You could never see the top.

There was the hustle and bustle of getting on the school bus. I used to go with neighbours and friends, we were all a bit damp and there was excited chatter because it was the last day before we broke up for half-term.

I can just see it so clearly now. I was sat at my desk. I had my English exercise book open - the exercise was to write a story to do with winter and I’d drawn a picture of a snowman.

I was sitting there at the desk when the noise came. I think it’s the noise that everybody remembers. The building shook, a crack appeared across the wall behind Miss Taylor’s desk and little puffs of dust came out of the crack as it appeared.

The lights were on very long flexes with white shades on them, they swung and jiggled from the force of it hitting. Outside, we could see the masonry and the debris falling. Miss Taylor just said ‘Get under your desks, keep calm’.

I’m not sure how long we were there, it didn’t seem that long. Miss Taylor said we were alright but the door was blocked. She could see a gap that we could get through. She said ‘Right, now line up, I want you to leave the classroom, I want you to walk straight out to the yard, don’t look back’.

The reason I wrote the poem was it came to a bit of a head last Thursday when a couple of work colleagues, who didn’t know that I’d been in the Aberfan disaster, happened to mention the programme that had been on the night before.