Hello,
During June 2008 I started graduate school. From Jan-May 2008 I lived and worked in Texas. In mid-May I moved to Massachusetts to start my program; I lived there until mid August and did not work. In September I moved to California to do an internship for the graduate program I am enrolled in. I am an intern at a local agency, but this internship is unpaid. I am officially enrolled in school in Massachusetts, not California. My question is where do I file taxes. I consider myself a Texas resident who is temporaly away because of school; I have never worked in another state. Thank you.
ElizabethC

You are part year resident of both Massachusetts and California. You did not have any income while you lived in these states so you do not report any income to these states.
You have Texas income but Texas does not have state tax.

If you are present in a state, then any income earned during this period, must be reported to the state.

To your resident state, you must report your worldwide income for the year. Read: Your U.S. Tax Return: Working or Living in Two or More states

ElizabethC - I agree with you; I think you should claim to be a full-year resident of TX. If you are enrolled full time in school in MA you are still a TX resident. Assuming that you will not be receiving a W-2 from anyone in either MA or CA, neither state has a claim on you. So file your federal form using your TX address, and no need to file any state taxes in either MA or CA.