Interview questions vary a lot from uni to uni, so you should make sure you're keeping abreast of educational news. You may be able to choose your own, but sometimes you will be asked about a specific issue.
Current issues I think you would need to be aware of:
- The new 9-1 GCSEs, especially the changes relating to your subject if you are secondary. Even if you are primary, you should probably be aware of these as it's such a big thing.
-Budgetary/financial issues facing schools.
-Teacher recruitment and retention issues (this can be quite hard to talk about at interview, and I wouldn't recommend bringing it up in your PS, but you should be prepared to potentially talk about it in interview).
-How wider societal issues (e.g. poverty) effect children and their education.