I live abroad and am traveling to the United States for college but will only be in the country for a year; how can I get an affordable, temporary mobile plan? Are there plans with international calling included?
There are a number of services available on a non-contract basis. The big companies like AT&T and T-Mobile both offer a variety of plans on a non-contract basis (which is who the company Mark posted serves as an agent for).
There are also a number of cell service brokers, such as TracFone, Net10, StraightTalk, who buy time on the big networks and re-sell it. Sometimes these re-sellers have better coverage, as they often have contracts with a couple of nationwide network providers.
I studied in the US for 10 months around 4 years ago now (2009-10). At that time I only had a Pay as You Go phone in my home country, so I just wanted to get a similar thing in the US. I got a cheap phone in Walmart that had a non-contract AT&T SIM card included. I think it was $30 but that actually included $20 of top-up (or whatever it is called in the US).
I only used it for calls and texts within the US (no data). For international calling, I used Skype on my laptop, or my home phone in an emergency as it actually worked out cheaper to use that one.
Of course, things may have changed since then, and you may have more requirements. Another student I went with had a smart phone from home, so he went into the AT&T store and discussed getting a contract SIM. He was then able to use data too.