The above poster is correct. Remember, when re-titling the membership, it requires a new deed and a waiver of ROFR from Disney, then filing with the appropriate county recorder/clerk. The loan/mortgage, if any, also has to be satisfied prior to re-titling. Also any reservations that are made would be canceled when Disney re-assigns the membership. Though more costly than doing it yourself, you may want to contact a timeshare closing company, they should be able to draw up any necessary papers and file them for you, for a fee, of course.
Once re-titled, the membership belongs to your children, you are no longer responsible for dues etc, as long as you are notshown as an owner on the new deed.
If you want to keep the membership in your name, until you leave it to them as part of your estate, then an adding them as an associate would be fine, but they would not get any membership perks or benefits, like the AP discount, if they no longer reside with you.