a phone for dad

I'd like to get a cell phone for both my parents... Mom would no doubt use it the most, but in the mornings it could be plugged in - charging in the front room. I won't say any more, but I could send Dad little text messages. He doesn't receive email. So far as I'm concerned thet's the only they need one... The phone would have to be prepaid, possibly as cheep as $10 a month...