when do catholic schools finish this term (catholic schools in Sydney Australia)?

Answer 1

It looks like Australian Catholic and public schools follow the same schedule: http://www.cecnsw.catholic.edu.au/

So it looks like the end of term will be December 21: http://www.dest.gov.au/portfolio_department/calendar_dates/school_term_dates_2006.htm#New_South_Wales

With love in Christ.

Answer 2

Cathlic schools like any other private schools can set there own dates and times for terms and school holidays.