I have an informal meeting with a school about volunteeribg with the view of doing my pgce in the future. What do I want to get out of it?

I emailed asking about work experience in a classroom. They've asked me to pop in for a chat about what I want. I'm guessing it'll be informal.
But what do I want? What relevant questions shall i ask?

I obviously want the the experience, I've never worked in a classroom before. But I have been working with schools & ks2 for quite a few years, in a residential/field studies/forest school type setting.
I need the classroom experience to get on to the pgce course.
But what should I be asking about in this meeting? What will they ask of me?
Thanks