This exercise is just about making sure you know how to use Sage. Login to a Sage Notebook server and create a new worksheet. Do some non-trivial computation, maybe a pretty plot or some gruesome numerical computation to an insane precision. Create an interesting list and experiment with it some. Maybe include some nicely formatted text or TeX using the included mini-word-processor of the Sage Notebook (hover until a blue bar appears between cells and then shift-click).
Use whatever mechanism your instructor has in place for submitting your work. Or save your worksheet and then trade worksheets via email (or another electronic method) with a classmate.