In case you do not know, the dunes are the largest continuous mobile sand dunes in the Southern Hemisphere. So, you won't want to miss this when you visit Port Stephens.
You have plenty to choose to do in this place: sand boarding, camel riding, 4WD experience, tour to Tin City and/or the Sygna wreck and other historical sites.
Many years ago before my child was born, I took the 4WD tour to Tin City, the Sygna wreck and sand-boarding, impressive!
My last trip on January 2015, I chose Port Stephens 4WD (portstephens4wd) Tour to do sand boarding and went straight to Anna Bay to swim and surf after. My child loved this day most in our trip in Port Stephens.
Here I would like to recommend Port Stephens 4WD Tour if you do not have a 4WD. They are very professional here and they could give you a discount on price if you call them. The good part was, we could freely stay on sand boarding as long as we liked and just took their 4WD run every 30 mins return back to Anna Bay. Just check the time table from them for the earliest and the last schedule of the day.