Why, of course, yes! I think this is a good idea. Aside from helping my house help in earning her means for a living, I would also love to assist her in expanding her financial assets and educate her about these matters. But of course, that is if she's open enough for this kind of investment. If she isn't then it's her call. :)
I've read about that in Bo Sanchez's book and it's a good thing that people are encouraging helpers to invest. However, in my case, I'm iffy about it since investments pose risk. I know that money lost greatly impacts not just their life but their families even. I don't want to be the cause of that.