I bought my cousin an 11" Macbook Air for $300 (refurbished, mid 2011 model) She's a bright kid, but living with her grandmother (not a great home situation) in rural Utah, and only had Internet access through her phone. Phones are usually more important than a computer, if you have to choose between the two (and don't have reliable Internet, or the skills/knowledge to set up Google Voice, or, say, VOIP software on your laptop), but a MacBook doesn't have to be more expensive than a smartphone.