The assignment is very general: choose a topic of interest within the domain of Human-Computer Interaction and carry out a cohesive, complete project based around it. The range of possible topics that you can choose among is very broad. However, the project you pick should incorporate a design element, a prototyping element, and either an evaluation component or a design for subsequent evaluation. The relative weights between these components is up to you to propose--for example, it is reasonable to design and prototype an interface, with the emphasis being on the "realism" of the prototype. It also is reasonable to try to design a mechanism to choose between two equally-plausible interface choices. Here the emphasis most likely would be on evaluation, with rudimentary implementation. I think the most interesting problems will be ones in which you identify and work with some "client" to develop a solution to one of their problems. Such clients can include organizations with which you are involved, work site, etc. You can propose to carry out a project as part of a larger effort. However the caution here is that you will need to be able to separate out the contribution made by this class' project from the rest.
You may work individually or in teams. A team can be as large as you want it to be, but correspondingly larger results will be expected from larger teams. It seems to me that the most productive teams are usually about two members in size.
All members of a team will receive the same grade for a group project. You will need to prepare a written project proposal, possibly with following discussion with the instructor, a written project checkpoint report, a final report (written), and an oral presentation (in class). All documents generated as part of the project should be turned in on paper and also collected on a Web site.
The following deadlines are relevant.
If you need suggestions on projects, please see me. There may be ideas associated with some ongoing research projects that can be examined.