I don't know about your school, but I had a similar project where I simply bs'd all the interview questions and answers.    Anyway, I think your questions are solid at first glance if you want them tailored to specific categories as you said you plan on doing. But if you want to do some comparisons for certain questions to show, for example, a trend, then you can ask them the same questions based on random samples of interviewees from each category.    You could also look up some simple research techniques for collecting valid survey data. Try not to become like the Princeton Review.