Treasury Work Experience

I want to do Economics at university, hence I am seeking a work experience placement at the Treasury. I'm planning on writing a letter, but not so sure what to include in order to make it ideal. Shall I mention why I deserve it, my A Levels, why i'm interested, etc?

What advice would anyone have?

Thanks

Yes that is the sort of thing you would want to mention, although I imagine that you would want to attach a copy of your CV as well. Good luck.

how old would u need to be for them to even consider u?

Well, I went to the Treasury website and it said it doesn't have a work experience programme, although it says if you write to them, they might consider you. They don't specify any requirements.