A seven-week study by the Wheeling Jesuit University Psychology Department showed as students increased their use of a peppermint scented pencil, their Grade Point Averages also increased.

— Read more at Wheeling Jesuit study reveals hidden GPA power in peppermint-scented pencils. Of course, maybe the students that lost the pencils immediately, or just forgot to have them on hand, were just less motivated than those that remembered to use them? But you might want to buy some peppermint Smencils anyway, and you can do so here (they also sell Smencils in a variety of other scents from Kinda Cola to Cinnamon to Bubblegum).