NOOO, HANG IN THERE TABLET!

It's unlikely if it will help, but have you checked to see if there's a possible driver update for it? It could also be that it's just old and has seen lots of use over the years, but maybe... there's an update for it. I don't I don't usually update the drivers of my devices, but you never know.

The pencil sketches look great though. They look like they're about to take a Calculus final exam! Lucky them! -_-