'Old skool' graffiti

I've often noticed these engravings on the bricks of this old school house when walking through the village. I should probably know more about the history of them (if any), I'm sure somebody at school could tell me.

After Clap & Sing this morning I did make it into school to arrange a meeting with the head. I guess I'll have to start thinking about work soon then :-(

Anya's not quite been herself today, hope she's back to her cheerful self tomorrow...