I don't know about green beans, but I freeze cabbage and peppers regularly. I slice them into strips, put into plastic bags w/zip-tops, press out as much air as possible, close the zip most of the way, then suck out the rest of the air w/my mouth and close the rest of the way. This works pretty well.
I guess in general, I would recommend preparing veggies to the size you want them to be for cooking, so that you don't have to deal w/cutting them in a half-frozen state but can just thaw by cooking.
One thing to remember about frozen veggies is that they won't be good to eat raw, because the texture will change. But if you intend on cooking them, they'll be fine.
Mama to a boy EnviroKid
10 years old and a little girl EnviroBaby
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