I have two villagers that have been farming FOREVER and they still aren't masters. I've been checking their skill level every so often and they haven't even improved in ages... Does anyone know a good way to get them to improve faster? Otherwise I think my poor villagers are going to starve to death!

Do you need a certain level in farming before they can become masters?

It depends what speed you're playing on.

I'm playing on 2x speed...Is that bad?

Nope. And no, they can become master farmers even if you have level 1 farming.