Australia / Australians travelling to poland.. re visa [4]

Hi... My Husband and I are off to Europe in November and we really wanted to spend new years in Krakow. We are unsure whether we need a visa. We will only be in Europe for a total of 45 days. Is poland part of the Schengen agreement. If not what do we do so when we get to poland at the end of december it is all organised. We want to stay in poland for 3 days.

Thanks

Jennifer