WordNet (r) 3.0 (2006):

term paper
    n 1: a composition intended to indicate a student's progress
         during a school term

Moby Thesaurus II by Grady Ward, 1.0:

40 Moby Thesaurus words for "term paper":
   article, causerie, descant, discourse, discussion, disquisition,
   dissertation, essay, etude, examination, excursus, exposition,
   feature, first approach, homily, introductory study, lucubration,
   memoir, monograph, morceau, note, outline, pandect, paper,
   paragraph, piece, preliminary study, prolegomenon, research paper,
   screed, sketch, special article, study, survey, theme, thesis,
   tract, tractate, treatise, treatment