KSHSAA Handbook 2007-2008 Edition
Rule 22 - Outside Competion
Art 1 - A student who is a member of a school athletic,scholars' bowl or debate squad effective Tuesday following Labor Day through Friday preceding Memorial Day may not participate as a member of an outside team or as an independent competitor in the same sport,scholars'bowl or debate activity.
Art 3 - A student becomes a member of a school's athletic squad, scholars' bowl or debate team when he or she first participates in a practice session.

Looks like it is legal to sit out the first week of practice.Go to CK Kickoff and start practice the 19th.