BBC World Service and now witness history with me, Alex Collins.

I'm taking you back to 1961, when a 10-year-old girl, Rosa Hernandez Acosta, tore adults decades

older than her to read and write.

She was one of a quarter of a million volunteers, known as Brigadistas.

He told me, little girl, you think you can teach us to read and write?

And I told him, of course, why not?

If you're willing and you try your hardest, you will see, you will learn.

That's Rosa Hernandez Acosta, it's early evening, and she's a week into her volunteering.

She's at the home of Teresa Avello.

She's just starting her lesson and teaching him in his family, and she's already running

into problems.

He just laughed at me.

But then one day, I took his hand to teach him to write the letter U, because it was really

hard for him.

I didn't give up on him until he learned it perfectly.

From that moment, he never doubted that I could teach them, and he gave me no more

comments.

On the contrary, if he was doing some work when I arrived, he would say, oh, here comes

Rosa.

Here comes Rosa, let's go.

And I never forget that.

He would give me compliments and bring me plantains and whatever else they had to offer.

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