For any interview, you should do your research on the company. For this position, make sure you understand the school's teaching philosophy and their mission statement. Read up on any recent news, because this will give you good ideas for questions and talking points.
They will likely ask you about your experience and education. If you don't have relevant work experience yet, draw examples from school or volunteering. Be prepared to give specific examples of your achievements.
Give your answers in "STAR" form.
Situation - the problem or issue you delt with
Task - what you needed to do
Action- how you handled the task
Result- the outcome. Make sure to focus on how the issue was resolved and how things were better because of the actions you took.
You should ask questions about the company, how your performance will be measured, what are some challenges you might expect, and the career path of the interviewer or other people who have the same position.
It is generally best to leave questions about salary or pay for after the first interview.