I am a senior studying computer science, but I am going to a career fair looking for an internship, not a full time job, since I am planning to pursue a master's degree in the computer science next year. Where do I put this planned master's degree in my resume to let employers know why I am looking for an internship and not a full-time job?
Preferably the cover letter, or the "Objectives" section of your resume. Be sure to explain that you are looking for an internship and not a full time job.
At a college career fair, most of the recruiters/companies will likely be very understanding of your situation, so when you meet face-to-face at the career fair, be sure to explain this as you hand them your resume.