Don't think about researching a specific topic, instead focus on looking for key terms in your project. For example I'm working on a project in my bioinformatics class and for my paper presentations the closest journals I could find that were related to topic were more related to other fields (ie. mathematics and linguistics). If you confine your research to a specific subject then you will miss ideas that you can utilize to make your project better. I find it useful to just google my key terms, or use google scholar. If you find a paper that looks interesting but isn't available google the specific title and usually there is at least one site that has it available.
For your topic some key ideas/terms come to mind are looking up ways to display the questions and programs that randomly generate text. Maybe look into test program that are already up to see how they choose the questions. Some sites may look into which questions were answered incorrectly and give more of those (especially if the site is there to help the student learn). If you want there to be more to picking the questions than just a random number generator then look into Artificial Intelligence journals.
I would also research the system that you mentioned is already available. Find out if there is a journal about it. If so look into the journals they site and also look into the journals that have sited this paper (google scholar for one mentions the journals that sited it). There may be a newer or older journal that is more similar to you project or has a specific feature you could use.
Overall don't go too specific. Keep your search broad. And good luck :D