We have the pass for Yanchep too, we like it as its nice and peaceful with free bbqs, roos and Koalas. Also the wierd cafe that sells lots of chocolate and apparently the pub there (Yanchep Inn ) does a good Sunday Carvery although haven't tried it myself.
Another nice place is Araluen Botanic park, I think its near Roleystone in the Hills. Lovely and peaceful too and there is a little train/tractor that you can ride on that kids love. Its bit of a drive if you live NOR though.
We have a lake near us (Lake Goollelal) with a good cycle path all the way around it so took my son for a walk yesterday, he had his trike, and we were warned by a couple about the snakes...well what did we come accross...a snake, right by the path!
I think we are going to try a day out at The Maze soon so will post if its any good.