It looks well gone, you could restore it but it will really cost you. Only you know if it's worth it. The other thing is I doubt whether you stopped growing at twelve years, so it will certainly be too small for to comfortably ride now.
It's the cost that puts me off if I'm honest. It has a value to me, but only to me.
I have a customer that loves old cars, and can afford to have them restored. He found the very first car that he owned while at university,
an Austin 7, that now has pride of place in his collection. He could just go out and buy whatever he wanted, but he doesn't. All his cars have
a family history. Isn't that nice.
As for size I was always an XL. When I was born I toped the scales at 10.5 lbs.
I remember when I rode the bike I had to stop at a grass bank or high kerb, or just jump off.
Kids today have a new one every five minutes; not so back then. Those that were lucky enough to have one bought for them, often s/h,
would have one they could grow into, fitted for a while, and then grow out of.
I believe frames are measured from crank centre to seat post pinch bolt. This is a 25 inch.
I'll need more time to deliberate.
Cheers,
Paul G