No subject

is sorting out what you mean by a conference/seminar?  Parents are not,
after all, interchangeable information units.  When you speak of govt
policy, what do you believe is the proper role for parents regarding same?
If your real interest is in the majority views of a given parent population,
modern polling techniques will do a far better job than any one-off event.
If your interest, however, is in the abstract notion that policy should be
commented upon and thus legitimized, you'll most likely do better through a
series of small group discussions through which parents can comment at
length and in the form they prefer, perhaps via anecdote and narrative.  You
may want to consider questions of confidentiality and also practical
incentives for participation.

Good luck
Drew Akason
Operations Officer
Interactivity Foundation