Fanatic viper - has centreboard and great learner board / all around family board.
http://www.fanatic.com/public/content/e554/e555/e5826/e5933/index_eng.html

Or the Mistral malibu
www.mistral.com/public/content/windsurfing/windsurfboards/malibu/index_eng.html

Mistral also do a prodigy - this is a little more perfomrance oriented (adjustable mast track position - on the fly) but you could still teach on it. Personally i think the viper and malibu would be better suited. There are other boards out there like the starboard go and start - but not as nice to sail generally in my opinion - I have sailed on the starboard go, the fanatic viper and the prodigy. For a family board the viper wins hands down.

Regarding getting them second hand - snowflakes chance in hell. These are so well liked that nobody sells them once they have them. You may find some big 140litre freeride / widestyle boards available- but again they sell straight away because there is such a demand. You will have to give serious thought about buying the board new.

If you want to try them out give simon a call at boardcrazy in brisbane 38916470 - he uses the vipers as his lesson boards. He may be able to find a second hand one - but don't hold your breath.

Hope this helps

SEW I have a Techno 283 that you may be interested in, review here

www.surfstore.co.uk/



Its good for learning and progressess to planing quite well and will carry up to a 9 m sail comfortably, I used a 8.4 Pryde V8 which was sweet on this board. Message me if you want to discuss.

For a sail, I also have a kids rig. Sadly my daughter is no longer interested in sailing So it must go .......

I have a starboard Z-class listed for sale on seabreeze. It has a centreboard and would be suitable for light wind sailing and learning and planes very well when the wind picks up. Take a look at the buy and sell.

I am often at Cootharaba. I can bring it up for you to try if you want.