Primary school memories

I was 11 , in Primary School back in England (I can't remember if that's what they called it then). That's going back quite a while.
Discipline was strict. School uniforms etc. Ours was grey with red and purple lines on the sweater V neck. Our jacket and school cap were purple , grey shirts and trousers and tie with red purple and grey diagonal lines. The girls had similar colours.
I sat in the back row next to a girl. I can't even remember her name but we got on well and used to talk during lessons by passing notes back and forth.
One day she surprised me by asking me on her note : "do you want to see my knickers ?".
I must have looked at her so disbelieving that she started laughing out loud and the teacher asked her if she wanted to share her joke with the rest of the class.
Anyway , I answered her note with :"YES" .
To which she started pulling up the front of her skirt under the table until her white flowery knickers were in view and after seeing my smiling look at her she quickly straightened her skirt.
11 is the kind of age , at least back then , that you know something happens down "there" but we were too innocent.
The following summer we moved.