Have you been to Darby Beach in Wilsons Prom?
It's a short 1km walk from the Darby Cark Park, just past the bridge that goes over the Darby River. Its an easy walk, except for one big hill that's soft sand right at the end.
The beach has rock formations at one end and cliffs with massive sand dune at the other end.
The waves are quite powerful there with a lot of pull, so unless your kids are very strong swimmers, keep a close reign on them.
It is a relatively unpopular spot, I have no idea why but there's rarely anyone else there! So do the short walk and enjoy the seclusion of your own private beach. Although, remember someone else may come along at any time, we have stumbled across a romantic couple there once, who obviously thought they were alone..... and who left rather embarrassed when they realised we were there too!