Hey john, sample questions for student visa can be found here:
http://www.abroadeducation.com.np/visa-preparation/possible-questions-visa.html

There is wide range of questions asked during a visa interview by a consular. You may be asked about any thing that concerns with you. You may be asked about your documents, your sponsors, your intentions, and even about your hobbies.

You can find visa interview questions here:
http://qna.educouncil.org/Visa_and_Immigration/nZxyNXyYnNy.html

Look at those questions and prepare for each and every question with your own answers. Good Luck.