Teaching Assistant Question:

The interviewer will ask about any difficult situations in your last job, related to work, which were solved by you by amicable means. This will prove to the interviewer whether you have any people skills. Make a list of such occurrences. Consult with a knowledgeable friend, or professor. Preferably someone who's working! Select the best and prepare to present the anecdote briefly, and succinctly.
Once the interviewer is satisfied that you have all the skills needed for a teacher's assistant, they may call you for a couple of more rounds before they finally select you for the job.