[Diogenes]

This all depends on if your district seeds its post-season tournament or not. The teams are not required to play one another during the season to be eligible for post-season play. If the schools in the district do vote to seed their tournament, then each school is required to play each other district school twice for seeding purposes. It's a patchwork across the state of what districts seed and what districts do not. Obviously, each school votes according to what it hopes will happen - traditionally strong programs will vote for seeding to play weaker opponents in the first round of the district, while weaker programs will vote for the random draw in hopes they'll be paired with another weak program in the first round of the tournament, all with the hopes of making it into the regional tournament as a district winner OR runner-up.

The conferences are an ancient relic from the old days when school did indeed play in conferences. These are basically just loose arrangements between schools to play one another now, often with a "conference tournament" that's basically just another in-season tournament for the involved school. These have no bearing on anything; they're entirely voluntary. Hope that clears it up a little.