Preparing for any school interview is the same...*Know the job and how you meet (and exceed!) the requirements/specification *Know the school...aims, ethos, recent changes etc *Know how you fit into those targets, team and progress. Observations are the same no matter what their purpose. They will want to see how you teach and will consider your learning objective(s), classroom management and the methods you choose. Then they'll try and decide (based on the snap shot you give them) if you will differentiate well, are creative and inspiring, etc. etc. Knowing their Ofsted report like the back of your hand will help. Let them know that you are ready to join the team and will be able to maintain their standards. Good luck, and if you only have a panel of 3 it should be quite easy to remember names and roles...try and use this to your advantage.