It is hard to question spot without knowing the context of the school. Do they see you as more of a careers co-ordinator etc. However I would spend some time lookng at the key stage criteria from the national curriculum and to have in your head the sort of things that might be age appropriate. Look at some of the free resources available on line so you have a clearer idea about what is available. www.nationwideeducation.co.uk/ is my current favourite for KS3 particularly; though it does assume easy IT access. NatWest also have a really well developed financial literacy scheme. Look at the PSHE Association website for more ideas. If you think they are going to look more at the careers side you need to establish what the current provision is so you aren't just repeating ideas that are in fact already in place. If it is a drop down day looking at enterprise you need to look for some providers/Dragons den type activities. If it is over a longer period look at things like young enterprise http://www.young-enterprise.org.uk/resources/PSHEKS3.pdf These are self-protective measures so you know what you might be taking on so can agree/disagree from there. Good Luck.