I've been our PTA Treasurer for 3 years now, don't have a Deputy. We're a small school (about 90 pupils), and there are 12 of us on the Committee. I was never given a job description.
I handle most of the finance for the fundraising, if I'm not at an event, someone else will collect the money and pass it to me, but if I'm there its my job by default. We run a big event in the summer, which involves sponsorships from individuals and companie, as well as funds on the day - that takes a fair bit of time, and we have a separate Committee to organise it, which I'm on as well.
I do all the banking, run the ledgers, manage the asset list, and produce the annual financial reports and Treasurer's Report, file with the Charity Commission, and work with the auditor.
I handle all payments, whether related to fundraising, or school requests. I check that the school requests link to the budgets/agreements/etc and circulate to Committee for payment. Have just put out the last batch for approval this weekend, as we need to get payment to the school on Monday (only managed to get the invoices on Friday!).
I keep a check on the school requests, and inform Committee of changes, additions etc, implications on funding limitations etc, ie - we're not a bottomless pit!
I take and present a financial report at every Committee meeting.
I create our fundraising expenditure budgets, and do the post-event analysis, so we can investigate areas we can decrease our costs.
All above, fairly standard I suppose - have never had the opportunity to speak to other Treasurers'.
Then I also:
Manage our Charity Commission registration
Manage our Lottery Registration with the Local Authority
Outside of my Treasurer role, I also do general PTA organising, doing etc.
Helping in the setting up and running of events
Cake baking - (but we don't sell to parents)
Just taken on some of our advertising
Minute taking when Secretary is absent
Ensuring we abide by our Constution and keep it up to date.
Would be interesting to know what other people do.
As I said, we're a small school PTA, so probably handle less money than other people. This year we've raised £13,000, and given the school £11,000.