Mike and Geoff beat me by a minute, but Kate, don't let that put you off an observing night. There are still plenty of objects to look at which would be of interest.
Perhaps get in touch with a local Astronomical club in your area and they may be able to assist with some club members to arrange a viewing night at your school? Try here:
http://www.iceinspace.com.au/clublistings.html#NSW
hoo roo,
Stephen