pick up a 25 ft macgregor with water ballast for $3000 or so.
it has enough room to take the family
and if you run aground just pump the ballast and refloat her.
Also the kids should be learning to sail.
I learned when I was 8, be sure to include them in everything you do as it will be their home too.
Read the books, take the courses but there is no beter way to learn then to actually be on the water.
I recently had a guy on my boat who was book learned. He knew every line ,every term, the right way to leave the dock depending on wind direction.
What everything on the boar was for and how to work it.
We went out, raised the sail and he was lost! Had no idea what to do, what line to use and he immediately turned the greatest color green you have ever seen. He couldn't associate what he was seeing with what he learned in a book.
Moral of the story is GET OUT THERE.
and to learn of the cruising life, pick up latts and atts magazine for info on the cruising life.
Oh one last thing. If your on a 4 year plan and the oldest is 14
HE'S NOT GOING TO WANT TO COME he will be 17 . New girlfriend, wants to graduate with his friends, he thinks its a stupid idea etc. you may want to shorten the plan a bit while he still wants to go.