Most of the buses and trains require advance payment by credit card. Rates for kids are less. Perimeter Transportation leaves from the airport. U.S. Maverick Coach Lines leaves from downtown. The dual passes allow you to ski either mountain on the same day.
Most people just pick one mountain at the beginning of the day.
You can also buy 3 day passes which turn out to be somewhat cheaper. If someone would like to volunteer to coordinate group discount tickets let me know, and I will put your email address here. Submissions can be in the form of an extended abstract or a full paper. Abstracts are generally four pages in length whereas full papers should be no longer than 10 pages. WCGS'97 is limited to 40 participants, on a first come, first served basis.